feat: in-app live log (SSE activity feed)

Turn the inert "Show Work" thinking panel into a real live activity log:
- lyra/logbus.py: thread-safe in-memory ring buffer other modules publish to
- chat.respond logs backend/model/embed per turn, recall counts, reply size;
  web layer logs chat errors
- server: replace the keep-alive /stream/thinking stub with /stream/logs, an
  SSE endpoint that replays the recent buffer then streams new events
- UI: repurpose the panel as a global "Live Log" — connects on load, renders
  level/time/msg/fields, drops the old per-session localStorage + dead popup

Every turn now shows its backend + model in-app, so local-vs-cloud (free vs
paid) is visible at a glance.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lyra/web/static/index.html

@@ -35,7 +35,7 @@
 
     <div class="mobile-menu-section">
       <h4>Actions</h4>
-      <button id="mobileThinkingStreamBtn">🧠 Show Work</button>
+      <button id="mobileThinkingStreamBtn">📜 Live Log</button>
       <button id="mobileSettingsBtn">⚙ Settings</button>
       <button id="mobileToggleThemeBtn">🌙 Toggle Theme</button>
       <button id="mobileForceReloadBtn">🔄 Force Reload</button>
@@ -68,7 +68,7 @@
       <select id="sessions"></select>
       <button id="newSessionBtn">➕ New</button>
       <button id="renameSessionBtn">✏️ Rename</button>
-      <button id="thinkingStreamBtn" title="Show thinking stream panel">🧠 Show Work</button>
+      <button id="thinkingStreamBtn" title="Show live activity log">📜 Live Log</button>
     </div>
 
     <!-- Status -->
@@ -80,10 +80,10 @@
     <!-- Chat messages -->
     <div id="messages"></div>
 
-    <!-- Thinking Stream Panel (collapsible) -->
+    <!-- Live Log Panel (collapsible) -->
     <div id="thinkingPanel" class="thinking-panel collapsed">
       <div class="thinking-header" id="thinkingHeader">
-        <span>🧠 Thinking Stream</span>
+        <span>📜 Live Log</span>
         <div class="thinking-controls">
           <span class="thinking-status-dot" id="thinkingStatusDot"></span>
           <button class="thinking-clear-btn" id="thinkingClearBtn" title="Clear events">🗑️</button>
@@ -92,8 +92,8 @@
       </div>
       <div class="thinking-content" id="thinkingContent">
         <div class="thinking-empty" id="thinkingEmpty">
-          <div class="thinking-empty-icon">🤔</div>
-          <p>Waiting for thinking events...</p>
+          <div class="thinking-empty-icon">📡</div>
+          <p>Waiting for activity...</p>
         </div>
       </div>
     </div>
@@ -509,22 +509,6 @@
 	  addMessage("system", `Session renamed to: ${newName}`);
 	});
 
-	// Thinking Stream button
-	document.getElementById("thinkingStreamBtn").addEventListener("click", () => {
-	  if (!currentSession) {
-		alert("Please select a session first");
-		return;
-	  }
-
-	  // Open thinking stream in new window
-	  const streamUrl = `http://10.0.0.41:8081/thinking-stream.html?session=${currentSession}`;
-	  const windowFeatures = "width=600,height=800,menubar=no,toolbar=no,location=no,status=no";
-	  window.open(streamUrl, `thinking_${currentSession}`, windowFeatures);
-
-	  addMessage("system", "🧠 Opened thinking stream in new window");
-	});
-
-
       // Settings Modal
       const settingsModal = document.getElementById("settingsModal");
       const settingsBtn = document.getElementById("settingsBtn");
@@ -705,113 +689,63 @@
       }
 
       function connectThinkingStream() {
-        if (!currentSession) return;
-
         // Close existing connection
         if (thinkingEventSource) {
           thinkingEventSource.close();
         }
 
-        // Load persisted events
-        loadThinkingEvents();
-
-        const url = `${CORTEX_BASE}/stream/thinking/${currentSession}`;
-        console.log('Connecting thinking stream:', url);
+        // The server replays its recent buffer on connect, so start from a clean panel.
+        thinkingContent.innerHTML = '';
+        thinkingEventCount = 0;
+        thinkingContent.appendChild(thinkingEmpty);
 
+        const url = `${RELAY_BASE}/stream/logs`;  // global server activity feed
         thinkingEventSource = new EventSource(url);
 
         thinkingEventSource.onopen = () => {
-          console.log('Thinking stream connected');
           thinkingStatusDot.className = 'thinking-status-dot connected';
         };
 
         thinkingEventSource.onmessage = (event) => {
           try {
-            const data = JSON.parse(event.data);
-            addThinkingEvent(data);
-            saveThinkingEvent(data); // Persist event
+            addLogEvent(JSON.parse(event.data));
           } catch (e) {
-            console.error('Failed to parse thinking event:', e);
+            console.error('Failed to parse log event:', e);
           }
         };
 
-        thinkingEventSource.onerror = (error) => {
-          console.error('Thinking stream error:', error);
+        thinkingEventSource.onerror = () => {
           thinkingStatusDot.className = 'thinking-status-dot disconnected';
-
-          // Retry connection after 2 seconds
-          setTimeout(() => {
-            if (thinkingEventSource && thinkingEventSource.readyState === EventSource.CLOSED) {
-              console.log('Reconnecting thinking stream...');
-              connectThinkingStream();
-            }
-          }, 2000);
+          // EventSource auto-reconnects; nothing to do here.
         };
       }
 
-      function addThinkingEvent(event) {
+      function escapeHtml(s) {
+        const d = document.createElement('div');
+        d.textContent = s == null ? '' : String(s);
+        return d.innerHTML;
+      }
+
+      function addLogEvent(event) {
         // Remove empty state if present
         if (thinkingEventCount === 0 && thinkingEmpty.parentNode) {
           thinkingContent.removeChild(thinkingEmpty);
         }
 
+        const level = event.level || 'info';
+        const time = new Date((event.ts || 0) * 1000).toLocaleTimeString();
+        const fields = event.fields || {};
+        const fieldStr = Object.keys(fields).length
+          ? Object.entries(fields).map(([k, v]) => `${k}=${v}`).join('  ')
+          : '';
+
         const eventDiv = document.createElement('div');
-        eventDiv.className = `thinking-event thinking-event-${event.type}`;
-
-        let icon = '';
-        let message = '';
-        let details = '';
-
-        switch (event.type) {
-          case 'connected':
-            icon = '✓';
-            message = 'Stream connected';
-            details = `Session: ${event.session_id}`;
-            break;
-
-          case 'thinking':
-            icon = '🤔';
-            message = event.data.message;
-            break;
-
-          case 'tool_call':
-            icon = '🔧';
-            message = event.data.message;
-            if (event.data.args) {
-              details = JSON.stringify(event.data.args, null, 2);
-            }
-            break;
-
-          case 'tool_result':
-            icon = '📊';
-            message = event.data.message;
-            if (event.data.result && event.data.result.stdout) {
-              details = `stdout: ${event.data.result.stdout}`;
-            }
-            break;
-
-          case 'done':
-            icon = '✅';
-            message = event.data.message;
-            if (event.data.final_answer) {
-              details = event.data.final_answer;
-            }
-            break;
-
-          case 'error':
-            icon = '❌';
-            message = event.data.message;
-            break;
-
-          default:
-            icon = '•';
-            message = JSON.stringify(event.data);
-        }
-
+        eventDiv.className = `log-line log-${level}`;
         eventDiv.innerHTML = `
-          <span class="thinking-event-icon">${icon}</span>
-          <span>${message}</span>
-          ${details ? `<div class="thinking-event-details">${details}</div>` : ''}
+          <span class="log-time">${escapeHtml(time)}</span>
+          <span class="log-level log-level-${level}">${escapeHtml(level)}</span>
+          <span class="log-msg">${escapeHtml(event.msg || '')}</span>
+          ${fieldStr ? `<span class="log-fields">${escapeHtml(fieldStr)}</span>` : ''}
         `;
 
         thinkingContent.appendChild(eventDiv);
@@ -819,47 +753,9 @@
         thinkingEventCount++;
       }
 
-      // Persist thinking events to localStorage
-      function saveThinkingEvent(event) {
-        if (!currentSession) return;
+      // (Log events are server-side and replayed on connect; no localStorage needed.)
 
-        const key = `thinkingEvents_${currentSession}`;
-        let events = JSON.parse(localStorage.getItem(key) || '[]');
-
-        // Keep only last 50 events to avoid bloating localStorage
-        if (events.length >= 50) {
-          events = events.slice(-49);
-        }
-
-        events.push({
-          ...event,
-          timestamp: Date.now()
-        });
-
-        localStorage.setItem(key, JSON.stringify(events));
-      }
-
-      // Load persisted thinking events
-      function loadThinkingEvents() {
-        if (!currentSession) return;
-
-        const key = `thinkingEvents_${currentSession}`;
-        const events = JSON.parse(localStorage.getItem(key) || '[]');
-
-        // Clear current display
-        thinkingContent.innerHTML = '';
-        thinkingEventCount = 0;
-
-        // Replay events
-        events.forEach(event => addThinkingEvent(event));
-
-        // Show empty state if no events
-        if (events.length === 0) {
-          thinkingContent.appendChild(thinkingEmpty);
-        }
-      }
-
-      // Update the old thinking stream button to toggle panel instead
+      // Live Log toggle button
       document.getElementById("thinkingStreamBtn").addEventListener("click", () => {
         thinkingPanel.classList.remove("collapsed");
         localStorage.setItem("thinkingPanelCollapsed", "false");
@@ -872,18 +768,10 @@
         localStorage.setItem("thinkingPanelCollapsed", "false");
       });
 
-      // Connect thinking stream when session loads
-      if (currentSession) {
-        connectThinkingStream();
-      }
+      // Connect to the global live log on page load.
+      connectThinkingStream();
 
-      // Reconnect thinking stream when session changes
-      const originalSessionChange = document.getElementById("sessions").onchange;
-      document.getElementById("sessions").addEventListener("change", () => {
-        setTimeout(() => {
-          connectThinkingStream();
-        }, 500); // Wait for session to load
-      });
+      // The live log is global (server-wide), so it does not reconnect on session change.
 
       // Cleanup on page unload
       window.addEventListener('beforeunload', () => {