feat(sfm): add SFM proxy router and event data page

- backend/routers/sfm.py: HTTP proxy to SFM backend (localhost:8200),
  mirrors the SLMM proxy pattern. SFM_BASE_URL env var for docker-compose.
  Catch-all /{path} forwards to SFM root (no /api/ prefix). 60s timeout.

- templates/sfm.html: full SFM dashboard with 5 tabs:
  Events (DB listing, filters by serial/date/false-trigger, flag/unflag FT),
  Units (known serials + stats, filter events by unit),
  Monitor Log (continuous monitoring intervals),
  ACH Sessions (call-home history),
  Live Device (TCP connect, device info cards, start/stop monitoring,
  push project config, download events from device, operation log).

- backend/main.py: import sfm router, include router, add GET /sfm route
- templates/base.html: add SFM Live Data nav link under Seismographs

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/main.py

@@ -18,7 +18,7 @@ logging.basicConfig(
 logger = logging.getLogger(__name__)
 
 from backend.database import engine, Base, get_db
-from backend.routers import roster, units, photos, roster_edit, roster_rename, dashboard, dashboard_tabs, activity, slmm, slm_ui, slm_dashboard, seismo_dashboard, projects, project_locations, scheduler, modem_dashboard
+from backend.routers import roster, units, photos, roster_edit, roster_rename, dashboard, dashboard_tabs, activity, slmm, slm_ui, slm_dashboard, seismo_dashboard, sfm, projects, project_locations, scheduler, modem_dashboard
 from backend.services.snapshot import emit_status_snapshot
 from backend.models import IgnoredUnit
 from backend.utils.timezone import get_user_timezone
@@ -97,6 +97,7 @@ app.include_router(slmm.router)
 app.include_router(slm_ui.router)
 app.include_router(slm_dashboard.router)
 app.include_router(seismo_dashboard.router)
+app.include_router(sfm.router)
 app.include_router(modem_dashboard.router)
 
 from backend.routers import settings
@@ -233,6 +234,12 @@ async def seismographs_page(request: Request):
     return templates.TemplateResponse("seismographs.html", {"request": request})
 
 
+@app.get("/sfm", response_class=HTMLResponse)
+async def sfm_page(request: Request):
+    """SFM live event data and device control dashboard"""
+    return templates.TemplateResponse("sfm.html", {"request": request})
+
+
 @app.get("/modems", response_class=HTMLResponse)
 async def modems_page(request: Request):
     """Field modems management dashboard"""

backend/routers/sfm.py

@@ -0,0 +1,130 @@
+"""
+SFM (Seismograph Field Module) Proxy Router
+
+Proxies requests from terra-view to the standalone SFM backend service.
+SFM runs on port 8200 and handles MiniMate Plus seismograph communication
+and event database queries.
+
+SFM endpoints are at root level (e.g. /db/units, /device/info) — no /api/ prefix.
+"""
+
+from fastapi import APIRouter, HTTPException, Request, Response
+import httpx
+import logging
+import os
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix="/api/sfm", tags=["sfm"])
+
+# SFM backend URL - configurable via environment variable
+SFM_BASE_URL = os.getenv("SFM_BASE_URL", "http://localhost:8200")
+
+
+@router.get("/health")
+async def check_sfm_health():
+    """
+    Check if the SFM backend service is reachable and healthy.
+    """
+    try:
+        async with httpx.AsyncClient(timeout=5.0) as client:
+            response = await client.get(f"{SFM_BASE_URL}/health")
+
+            if response.status_code == 200:
+                data = response.json()
+                return {
+                    "status": "ok",
+                    "sfm_status": "connected",
+                    "sfm_url": SFM_BASE_URL,
+                    "sfm_response": data
+                }
+            else:
+                return {
+                    "status": "degraded",
+                    "sfm_status": "error",
+                    "sfm_url": SFM_BASE_URL,
+                    "detail": f"SFM returned status {response.status_code}"
+                }
+
+    except httpx.ConnectError:
+        return {
+            "status": "error",
+            "sfm_status": "unreachable",
+            "sfm_url": SFM_BASE_URL,
+            "detail": "Cannot connect to SFM backend. Is it running?"
+        }
+    except Exception as e:
+        return {
+            "status": "error",
+            "sfm_status": "error",
+            "sfm_url": SFM_BASE_URL,
+            "detail": str(e)
+        }
+
+
+# HTTP catch-all — proxies everything else to SFM backend
+@router.api_route("/{path:path}", methods=["GET", "POST", "PUT", "DELETE", "PATCH"])
+async def proxy_to_sfm(path: str, request: Request):
+    """
+    Proxy all requests to the SFM backend service.
+
+    SFM endpoints have no /api/ prefix — target URL is {SFM_BASE_URL}/{path}.
+    Timeout is 60s to allow for live device round-trips (event downloads can
+    take 30-45s for a full event list).
+    """
+    # Build target URL — SFM endpoints live at root, not /api/
+    target_url = f"{SFM_BASE_URL}/{path}"
+
+    # Forward query params
+    query_params = dict(request.query_params)
+
+    # Read body for mutation requests
+    body = None
+    if request.method in ["POST", "PUT", "PATCH"]:
+        try:
+            body = await request.body()
+        except Exception as e:
+            logger.error(f"Failed to read request body: {e}")
+            body = None
+
+    # Strip hop-by-hop headers
+    headers = dict(request.headers)
+    headers_to_exclude = ["host", "content-length", "transfer-encoding", "connection"]
+    proxy_headers = {k: v for k, v in headers.items() if k.lower() not in headers_to_exclude}
+
+    logger.info(f"Proxying {request.method} {path} → SFM: {target_url}")
+
+    try:
+        async with httpx.AsyncClient(timeout=60.0) as client:
+            response = await client.request(
+                method=request.method,
+                url=target_url,
+                params=query_params,
+                headers=proxy_headers,
+                content=body
+            )
+            return Response(
+                content=response.content,
+                status_code=response.status_code,
+                headers=dict(response.headers),
+                media_type=response.headers.get("content-type")
+            )
+
+    except httpx.ConnectError:
+        logger.error(f"Failed to connect to SFM backend at {SFM_BASE_URL}")
+        raise HTTPException(
+            status_code=503,
+            detail=f"SFM backend service unavailable. Is SFM running on {SFM_BASE_URL}?"
+        )
+    except httpx.TimeoutException:
+        logger.error(f"Timeout connecting to SFM backend at {SFM_BASE_URL}")
+        raise HTTPException(
+            status_code=504,
+            detail="SFM backend timeout"
+        )
+    except Exception as e:
+        logger.error(f"Error proxying to SFM: {e}")
+        raise HTTPException(
+            status_code=500,
+            detail=f"Failed to proxy request to SFM: {str(e)}"
+        )