Dashboard web FastAPI + Chart.js

- 4 vues : spectre temps reel, historique detections, background, timeline CPS
- API REST : /api/status, /api/spectrum/current, /api/spectrum/difference,
  /api/background, /api/background/spectrum, /api/history, /api/cps/timeline
- Frontend vanilla JS + Chart.js (pas de Node.js, leger pour Pi 4)
- Moniteur modifie pour exporter son etat dans /data/monitor_state.json
  et le CPS dans /data/cps_log.jsonl chaque cycle
- Nouveau conteneur Docker 'web' sur port 8080
- Theme sombre, calibration energie (E = 0.33 + 2.97 * canal)

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

web/app/routers/cps.py

@@ -0,0 +1,38 @@
+from fastapi import APIRouter, Query
+from app.config import CPS_LOG_PATH
+import json
+
+router = APIRouter()
+
+
+@router.get("/timeline")
+async def get_cps_timeline(hours: int = Query(default=24, ge=1, le=720)):
+    """CPS data points for the last N hours."""
+    if not CPS_LOG_PATH.exists():
+        return {"data_points": [], "hours": hours}
+
+    from datetime import datetime, timedelta
+
+    cutoff = datetime.now() - timedelta(hours=hours)
+    data_points = []
+
+    try:
+        with open(CPS_LOG_PATH) as f:
+            for line in f:
+                line = line.strip()
+                if not line:
+                    continue
+                try:
+                    entry = json.loads(line)
+                    ts = datetime.fromisoformat(entry["ts"])
+                    if ts >= cutoff:
+                        data_points.append(entry)
+                except (json.JSONDecodeError, KeyError, ValueError):
+                    continue
+    except OSError:
+        return {"data_points": [], "hours": hours}
+
+    return {
+        "hours": hours,
+        "data_points": data_points,
+    }