sfm_webapp: default to Database view + sortable columns + inline waveform plot

Three UX upgrades to the main SFM webapp at /, all reinforcing the
'browse stored events' flow as the primary entry point:

1. Default section is now Database, not Live Device.  Most users land
   here to look at stored events; Live Device is opt-in (click the tab
   to talk to a unit).  Initial history + units fetch fires on first
   paint so the table is populated when the page loads.

2. History table columns are sortable.  Click any header to sort:
   timestamp, serial, per-channel PPV (Tran/Vert/Long), PVS, mic dB(L),
   project, client, type, key.  Default direction varies by column type
   (desc for numbers + timestamps, asc for text).  Sort arrows appear
   in the active column header.  Headers are sticky so they stay
   visible while scrolling.

3. Click-event-to-see-waveform.  The existing sidecar review modal now
   renders the 4-channel waveform plot inline at the top, fetched from
   /db/events/{id}/waveform.json in parallel with the sidecar fetch.
   Channels stacked MicL / Long / Vert / Tran (Instantel printout
   order), shared bottom time axis, dashed trigger line + triangle
   markers at t=0, zero baseline with "0.0" label on the right edge,
   peak callouts per channel.  Charts cleaned up on modal close.

Resolves the "where is the viewer" surprise — operators no longer need
to know about the /events route to see waveforms.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -8,7 +8,8 @@ All notable changes to seismo-relay are documented here.
 
 ### Added
 
-- **Stored-event browser** — new standalone HTML page at `GET /events` (`sfm/event_browser.html`).  Pick a serial from the unit dropdown, scroll through that unit's events (newest-first), click any event to render its decoded waveform via the existing `/db/events/{id}/waveform.json` endpoint.  Dark-themed Chart.js viewer, channels stacked vertically (Tran / Vert / Long / MicL — Instantel printout order, designed PDF-export-ready), trigger line at t=0, peak labels, search/filter, false-trigger flag honored.  Companion to the existing live-device viewer at `/waveform`; the two routes are now clearly delineated in their docstrings.
+- **SFM webapp now opens to Database view by default** and the History table is fully interactive.  Click any column header to sort ascending / descending (timestamp, serial, per-channel PPV, PVS, mic dB(L), project, client, record type, key — all sortable).  Click any event row to open the event modal, which now renders a **4-channel waveform plot inline** (MicL / Long / Vert / Tran stacked, Instantel-printout order) alongside the existing sidecar review fields.  Headers are sticky so the columns stay visible while scrolling long event lists.  No more "where is the viewer" — pick a unit from the filter dropdown, scan the table, click the event, see the waveform.
+- **Stored-event browser** — new standalone HTML page at `GET /events` (`sfm/event_browser.html`).  Pick a serial from the unit dropdown, scroll through that unit's events (newest-first), click any event to render its decoded waveform via the existing `/db/events/{id}/waveform.json` endpoint.  Dark-themed Chart.js viewer, channels stacked vertically (MicL / Long / Vert / Tran — Instantel printout order, designed PDF-export-ready), trigger line at t=0, peak labels, search/filter, false-trigger flag honored.  Companion to the existing live-device viewer at `/waveform`; the two routes are now clearly delineated in their docstrings.  The webapp's inline plot at `/` is the primary path; `/events` remains a useful diagnostic when you want just a viewer.
 - **Histogram body codec — uint8 peak count fix.**  Per-channel peak fields at `block[6]/[10]/[14]/[18]` are `uint8`, not `uint16 LE` spanning `block[6:8]` etc.  The original interpretation was byte-exact on the N844 fixture corpus only because every annotation byte (`block[7]/[11]/[15]/[19]`) in those fixtures was zero.  On non-N844 events with non-zero annotation bytes (observed across BE9558 Tran-drift and BE18003 Histogram+Continuous units), the old interpretation produced peaks up to 268 in/s per channel and 35× inflated PVS sums when first deployed to prod (rolled back same day; properly fixed in this release).  Cross-correlated against BW's per-interval ASCII export on K558 / T003 / N599 / N844 corpora — 100% byte-exact on T/V/L, 99%+ on M (sub-precision rounding).  Annotation byte preserved on each record as `record["annotations"]` for future RE.  Verified against ~3,500 blocks across 5 in-repo fixtures + a synthetic K558 interval-12 regression block.
 - **`apply_bw_report_dict_to_event` helper** in `minimateplus.event_file_io`.  Mirror of `apply_report_to_event` for the projected sidecar dict shape — used by the backfill path, which has the preserved `bw_report` block but not the original `.TXT` file.  BW's reported peaks (and `sample_rate` / `record_time`) now win over codec output during `--force` backfill, matching ingest-path behavior.
 - **`scripts/check_bw_report_preservation.py`** — two-step snapshot/diff tool to verify that `backfill_sidecars.py` doesn't wipe the `bw_report` block from existing sidecars.  Classifies every sidecar as PRESERVED / CHANGED / WIPED / STILL_MISSING / NEW / ADDED / REMOVED.  Exit code 1 if any WIPED or CHANGED entries are found, so it can gate a CI step or deploy script.

sfm/sfm_webapp.html

@@ -499,6 +499,20 @@
       text-align: left;
       border-bottom: 1px solid var(--border);
       white-space: nowrap;
+      position: sticky;
+      top: 0;
+      z-index: 1;
+    }
+    table.db-table thead th[data-sort]:hover {
+      background: var(--border2);
+      color: var(--text);
+    }
+    table.db-table thead th .sort-arrow {
+      display: inline-block;
+      width: 10px;
+      color: var(--accent, #58a6ff);
+      font-weight: 900;
+      text-align: center;
     }
     table.db-table tbody tr { border-bottom: 1px solid var(--border2); }
     table.db-table tbody tr:last-child { border-bottom: none; }
@@ -758,7 +772,9 @@
       overflow: hidden;
       min-height: 0;
     }
-    #section-db { display: none; }
+    /* Default to Database view on page load — most users are here to
+       browse stored events, not connect to a live unit. */
+    #section-live { display: none; }
 
     /* ── Live connect bar (host/port/connect, live section only) ── */
     #live-connect-bar {
@@ -792,8 +808,8 @@
   </div>
   <div class="hdr-sep"></div>
   <div class="section-switcher">
-    <button class="section-btn active" onclick="switchSection('live')">Live Device</button>
+    <button class="section-btn"        onclick="switchSection('live')">Live Device</button>
-    <button class="section-btn"        onclick="switchSection('db')">Database</button>
+    <button class="section-btn active" onclick="switchSection('db')">Database</button>
   </div>
   <div class="hdr-sep"></div>
   <label class="force-toggle" id="force-toggle"
@@ -1224,18 +1240,18 @@
     <div class="db-table-wrap" id="hist-table-wrap" style="display:none">
       <table class="db-table" id="hist-table">
         <thead>
-          <tr>
+          <tr id="hist-header-row">
-            <th>Timestamp</th>
+            <th data-sort="timestamp">Timestamp <span class="sort-arrow"></span></th>
-            <th>Serial</th>
+            <th data-sort="serial">Serial <span class="sort-arrow"></span></th>
-            <th>Tran (in/s)</th>
+            <th data-sort="tran_ppv">Tran (in/s) <span class="sort-arrow"></span></th>
-            <th>Vert (in/s)</th>
+            <th data-sort="vert_ppv">Vert (in/s) <span class="sort-arrow"></span></th>
-            <th>Long (in/s)</th>
+            <th data-sort="long_ppv">Long (in/s) <span class="sort-arrow"></span></th>
-            <th>PVS (in/s)</th>
+            <th data-sort="peak_vector_sum">PVS (in/s) <span class="sort-arrow"></span></th>
-            <th>Mic (dBL)</th>
+            <th data-sort="mic_ppv">Mic (dBL) <span class="sort-arrow"></span></th>
-            <th>Project</th>
+            <th data-sort="project">Project <span class="sort-arrow"></span></th>
-            <th>Client</th>
+            <th data-sort="client">Client <span class="sort-arrow"></span></th>
-            <th>Type</th>
+            <th data-sort="record_type">Type <span class="sort-arrow"></span></th>
-            <th>Key</th>
+            <th data-sort="waveform_key">Key <span class="sort-arrow"></span></th>
             <th></th>
           </tr>
         </thead>
@@ -1388,7 +1404,9 @@ function deviceParams() {
 }
 
 // ── Section switching ─────────────────────────────────────────────────────────
-let currentSection = 'live';
+// Default to Database — most users land here to browse stored events.
+// Live Device is opt-in (click the tab to talk to a unit).
+let currentSection = 'db';
 
 function switchSection(name) {
   currentSection = name;
@@ -2333,6 +2351,12 @@ async function _fetchUnits() {
 }
 
 // ── History tab ────────────────────────────────────────────────────────────────
+// Module-level state for the history table — preserved across re-sorts.
+// We sort + re-render without re-fetching.
+let _histEvents = [];
+let _histSortKey = 'timestamp';
+let _histSortDir = 'desc';   // 'asc' | 'desc'
+
 async function loadHistory() {
   histLoaded = true;
   const serial  = document.getElementById('hist-serial-filter').value;
@@ -2364,10 +2388,20 @@ async function loadHistory() {
   _populateSerialDropdown('monlog-serial-filter');
   _populateSerialDropdown('sess-serial-filter');
 
-  document.getElementById('hist-count').textContent = `${events.length} event${events.length !== 1 ? 's' : ''}`;
+  _histEvents = events;
+  renderHistTable();
+}
+
+// Re-render the history table from `_histEvents` using the current sort
+// state.  Pulled out of `loadHistory` so column-header clicks can re-sort
+// in-memory without re-fetching from the server.
+function renderHistTable() {
+  const events = _histEvents;
+  document.getElementById('hist-count').textContent =
+    `${events.length} event${events.length !== 1 ? 's' : ''}`;
+
   const tbody = document.getElementById('hist-tbody');
   tbody.innerHTML = '';
-
   if (events.length === 0) {
     document.getElementById('hist-empty').style.display = 'block';
     document.getElementById('hist-table-wrap').style.display = 'none';
@@ -2376,11 +2410,31 @@ async function loadHistory() {
   document.getElementById('hist-empty').style.display = 'none';
   document.getElementById('hist-table-wrap').style.display = 'block';
 
-  for (const ev of events) {
+  // Sort in-place by current key + direction.  Nulls sink to the bottom
+  // regardless of direction.
+  const k = _histSortKey;
+  const dir = _histSortDir === 'asc' ? 1 : -1;
+  const sorted = [...events].sort((a, b) => {
+    const av = a[k], bv = b[k];
+    if (av == null && bv == null) return 0;
+    if (av == null) return 1;
+    if (bv == null) return -1;
+    if (typeof av === 'number' && typeof bv === 'number') return (av - bv) * dir;
+    return String(av).localeCompare(String(bv)) * dir;
+  });
+
+  // Update arrow indicators in the headers
+  document.querySelectorAll('#hist-header-row th[data-sort]').forEach(th => {
+    const arrow = th.querySelector('.sort-arrow');
+    if (!arrow) return;
+    arrow.textContent = th.dataset.sort === k ? (_histSortDir === 'asc' ? '↑' : '↓') : '';
+  });
+
+  for (const ev of sorted) {
     const tr = document.createElement('tr');
     const pvs = ev.peak_vector_sum;
     tr.classList.add('clickable');
-    tr.title = 'Click to review (open sidecar editor)';
+    tr.title = 'Click to view waveform + sidecar';
     tr.dataset.eventId = ev.id;
     tr.innerHTML = `
       <td>${_fmtTs(ev.timestamp)}</td>
@@ -2408,6 +2462,28 @@ async function loadHistory() {
   }
 }
 
+// Click a column header → toggle sort.  Click another → set sort to that column.
+document.addEventListener('DOMContentLoaded', () => {
+  const headerRow = document.getElementById('hist-header-row');
+  if (!headerRow) return;
+  headerRow.querySelectorAll('th[data-sort]').forEach(th => {
+    th.style.cursor = 'pointer';
+    th.style.userSelect = 'none';
+    th.addEventListener('click', () => {
+      const k = th.dataset.sort;
+      if (_histSortKey === k) {
+        _histSortDir = _histSortDir === 'asc' ? 'desc' : 'asc';
+      } else {
+        _histSortKey = k;
+        // Default direction: 'desc' for numbers + timestamps (biggest/newest first),
+        // 'asc' for text columns (alphabetical).
+        _histSortDir = ['serial','project','client','record_type','waveform_key'].includes(k) ? 'asc' : 'desc';
+      }
+      renderHistTable();
+    });
+  });
+});
+
 // ── Sidecar review modal ───────────────────────────────────────────────────────
 //
 // Opens on row click in the History table.  Loads the .sfm.json sidecar
@@ -2430,23 +2506,214 @@ async function openSidecarModal(eventId) {
   document.getElementById('sc-edit-ft').checked = false;
   document.getElementById('sc-edit-reviewer').value = '';
   document.getElementById('sc-edit-notes').value = '';
+  // Reset waveform area
+  document.getElementById('sc-waveform-status').textContent = 'Loading waveform…';
+  document.getElementById('sc-waveform-charts').innerHTML = '';
+  _destroyScCharts();
 
-  try {
+  // Sidecar + waveform fetched in parallel — neither blocks the other.
-    const r = await fetch(`${api()}/db/events/${eventId}/sidecar`);
+  const sidecarP  = fetch(`${api()}/db/events/${eventId}/sidecar`)
-    if (!r.ok) {
+    .then(async r => {
-      const e = await r.json().catch(() => ({}));
+      if (!r.ok) { const e = await r.json().catch(() => ({})); throw new Error(e.detail || r.statusText); }
-      throw new Error(e.detail || r.statusText);
+      return r.json();
-    }
+    });
-    const data = await r.json();
+  const waveformP = fetch(`${api()}/db/events/${eventId}/waveform.json`)
+    .then(async r => {
+      if (r.status === 404) return null;  // no waveform available — render empty state
+      if (!r.ok) { const e = await r.json().catch(() => ({})); throw new Error(e.detail || r.statusText); }
+      return r.json();
+    });
+
+  // Sidecar usually loads first (smaller payload).  Each one renders
+  // independently so the modal becomes useful as soon as either lands.
+  sidecarP.then(data => {
     _scCurrentSidecar = data;
     _renderSidecar(data);
     document.getElementById('sc-status').textContent = '';
-  } catch (e) {
+  }).catch(e => {
     document.getElementById('sc-status').className = 'sc-status error';
-    document.getElementById('sc-status').textContent = `Load failed: ${e.message}`;
+    document.getElementById('sc-status').textContent = `Sidecar load failed: ${e.message}`;
+  });
+
+  waveformP.then(data => {
+    if (!data) {
+      document.getElementById('sc-waveform-status').textContent = 'No waveform data for this event.';
+      return;
+    }
+    _renderScWaveform(data);
+  }).catch(e => {
+    document.getElementById('sc-waveform-status').textContent = `Waveform load failed: ${e.message}`;
+  });
+}
+
+// ── Sidecar-modal waveform plot ──────────────────────────────────────────────
+// Renders the 4-channel decoded waveform fetched from
+// /db/events/{id}/waveform.json — MicL on top, Tran on bottom (matches
+// Instantel BW Event Report layout).  Uses Chart.js (loaded at the top of
+// the page for the live-device viewer).
+const _SC_CHANNEL_COLORS = {
+  MicL: '#e066ff',
+  Long: '#3a80ff',
+  Vert: '#3fb950',
+  Tran: '#f85149',
+};
+const _SC_CHANNEL_ORDER = ['MicL', 'Long', 'Vert', 'Tran'];
+let _scCharts = {};
+
+function _destroyScCharts() {
+  Object.values(_scCharts).forEach(c => { try { c.destroy(); } catch {} });
+  _scCharts = {};
+}
+
+function _renderScWaveform(data) {
+  document.getElementById('sc-waveform-status').textContent = '';
+  const chartsDiv = document.getElementById('sc-waveform-charts');
+  chartsDiv.innerHTML = '';
+  _destroyScCharts();
+
+  const channels = data.channels || {};
+  const timeAxis = data.time_axis || null;
+  const triggerMs = data.trigger_ms ?? 0;
+
+  // Which channels have data — determines which one renders the shared bottom axis.
+  const withData = _SC_CHANNEL_ORDER.filter(ch =>
+    channels[ch] && (channels[ch].values || []).length > 0
+  );
+  const lastCh = withData[withData.length - 1];
+
+  for (const ch of _SC_CHANNEL_ORDER) {
+    const chData = channels[ch];
+    if (!chData) continue;
+    const values = chData.values || [];
+
+    const wrap = document.createElement('div');
+    wrap.style.cssText = 'background:var(--surface);border:1px solid var(--border2);border-radius:6px;padding:6px 30px 4px 10px';
+    const lbl = document.createElement('div');
+    lbl.style.cssText = `font-size:10px;font-weight:600;letter-spacing:0.05em;text-transform:uppercase;margin-bottom:2px;color:${_SC_CHANNEL_COLORS[ch]};display:flex;justify-content:space-between`;
+    const peakStr = chData.peak != null
+      ? `peak ${(typeof chData.peak === 'number' ? chData.peak.toExponential(3) : chData.peak)} ${chData.unit || ''}`
+      : '';
+    lbl.innerHTML = `<span>${ch}</span><span style="color:var(--text-dim);font-weight:normal">${peakStr}</span>`;
+    wrap.appendChild(lbl);
+
+    if (values.length === 0) {
+      const e = document.createElement('div');
+      e.style.cssText = 'height:80px;display:flex;align-items:center;justify-content:center;color:var(--text-dim);font-size:11px';
+      e.textContent = 'no samples decoded';
+      wrap.appendChild(e);
+      chartsDiv.appendChild(wrap);
+      continue;
+    }
+
+    const canvasWrap = document.createElement('div');
+    canvasWrap.style.cssText = 'position:relative;height:100px';
+    const canvas = document.createElement('canvas');
+    canvasWrap.appendChild(canvas);
+    wrap.appendChild(canvasWrap);
+    chartsDiv.appendChild(wrap);
+
+    // Build time axis.  Prefer server-provided time_axis; else derive from sample_rate.
+    let times;
+    if (timeAxis && timeAxis.length === values.length) {
+      times = timeAxis;
+    } else {
+      const sr = data.sample_rate || 1024;
+      times = values.map((_, i) => (i / sr * 1000 - triggerMs));
+    }
+
+    // Downsample for rendering when very long.
+    const MAX = 3000;
+    let rT = times, rV = values;
+    if (values.length > MAX) {
+      const step = Math.ceil(values.length / MAX);
+      rT = times.filter((_, i) => i % step === 0);
+      rV = values.filter((_, i) => i % step === 0);
+    }
+    const showX = (ch === lastCh);
+
+    _scCharts[ch] = new Chart(canvas, {
+      type: 'line',
+      data: {
+        labels: rT.map(t => (typeof t === 'number' ? t.toFixed(2) : t)),
+        datasets: [{
+          data: rV,
+          borderColor: _SC_CHANNEL_COLORS[ch],
+          borderWidth: 1,
+          pointRadius: 0,
+          tension: 0,
+        }],
+      },
+      options: {
+        animation: false, responsive: true, maintainAspectRatio: false,
+        plugins: {
+          legend: { display: false },
+          tooltip: {
+            mode: 'index', intersect: false,
+            callbacks: {
+              title: items => `t = ${items[0].label} ms`,
+              label: item => `${ch}: ${item.raw} ${chData.unit || ''}`,
+            },
+          },
+        },
+        scales: {
+          x: {
+            type: 'category', display: showX,
+            ticks: { color: '#484f58', maxTicksLimit: 8, maxRotation: 0, callback: (v, i) => rT[i] + ' ms' },
+            grid:  { color: '#21262d', drawTicks: showX },
+          },
+          y: {
+            ticks: { color: '#484f58', maxTicksLimit: 4 },
+            grid:  { color: '#21262d' },
+            title: { display: true, text: chData.unit || '', color: '#484f58', font: { size: 9 } },
+          },
+        },
+      },
+      plugins: [{
+        id: 'overlays',
+        afterDraw(chart) {
+          const ctx = chart.ctx, x = chart.scales.x, y = chart.scales.y;
+          // Dashed trigger line at t=0
+          const zi = rT.findIndex(t => parseFloat(t) >= 0);
+          if (zi >= 0) {
+            const px = x.getPixelForValue(zi);
+            ctx.save();
+            ctx.beginPath(); ctx.moveTo(px, y.top); ctx.lineTo(px, y.bottom);
+            ctx.strokeStyle = 'rgba(248,81,73,0.8)'; ctx.lineWidth = 1.2;
+            ctx.setLineDash([4, 3]); ctx.stroke(); ctx.restore();
+            // Triangle markers above and below the chart
+            ctx.save();
+            ctx.fillStyle = '#f85149';
+            ctx.beginPath();
+            ctx.moveTo(px - 4, y.top - 7); ctx.lineTo(px + 4, y.top - 7); ctx.lineTo(px, y.top - 1);
+            ctx.closePath(); ctx.fill();
+            ctx.beginPath();
+            ctx.moveTo(px - 4, y.bottom + 7); ctx.lineTo(px + 4, y.bottom + 7); ctx.lineTo(px, y.bottom + 1);
+            ctx.closePath(); ctx.fill();
+            ctx.restore();
+          }
+          // Zero baseline + label
+          const zy = y.getPixelForValue(0);
+          if (zy >= y.top && zy <= y.bottom) {
+            ctx.save();
+            ctx.strokeStyle = '#30363d'; ctx.lineWidth = 0.8;
+            ctx.setLineDash([2, 2]);
+            ctx.beginPath(); ctx.moveTo(x.left, zy); ctx.lineTo(x.right, zy); ctx.stroke();
+            ctx.restore();
+            ctx.save();
+            ctx.fillStyle = '#c9d1d9'; ctx.font = '10px monospace';
+            ctx.textAlign = 'left'; ctx.textBaseline = 'middle';
+            ctx.fillText('0.0', x.right + 6, zy);
+            ctx.restore();
+          }
+        },
+      }],
+    });
   }
 }
 
+// Make sure charts get cleaned up when the modal closes.
+function _scCleanupOnClose() { _destroyScCharts(); }
+
 function _renderSidecar(data) {
   const ev   = data.event        || {};
   const pv   = data.peak_values  || {};
@@ -2512,6 +2779,7 @@ function closeSidecarModal() {
   document.getElementById('sc-overlay').classList.remove('visible');
   _scCurrentEventId = null;
   _scCurrentSidecar = null;
+  _destroyScCharts();
 }
 
 function onSidecarOverlayClick(e) {
@@ -2722,6 +2990,13 @@ document.addEventListener('keydown', e => {
 // hit localhost:8200, 10.0.0.44:8200, or anything else.
 document.getElementById('api-base').value = window.location.origin;
 
+// We default to Database view → trigger initial history + units load
+// (switchSection handles this when clicked, but we never click on first paint).
+if (currentSection === 'db') {
+  if (!histLoaded)  loadHistory();
+  if (!unitsLoaded) loadUnits();
+}
+
 // Press Enter in any live connect field to connect
 ['dev-host','dev-port'].forEach(id => {
   document.getElementById(id)?.addEventListener('keydown', e => { if (e.key === 'Enter') connectUnit(); });
@@ -2738,6 +3013,12 @@ document.getElementById('api-base').value = window.location.origin;
       <button class="sc-close" onclick="closeSidecarModal()">×</button>
     </div>
     <div class="sc-body">
+      <!-- Waveform plot — 4 channels stacked (MicL, Long, Vert, Tran) — -->
+      <div class="sc-section" id="sc-section-waveform">
+        <h4>Waveform</h4>
+        <div id="sc-waveform-status" style="color:var(--text-dim);font-size:11px;margin-bottom:6px">Loading…</div>
+        <div id="sc-waveform-charts" style="display:flex;flex-direction:column;gap:6px"></div>
+      </div>
       <div class="sc-section">
         <h4>Event</h4>
         <dl class="sc-grid">