Add delete with confirmation for trips and dashcam

- Confirmation modal in server base.html (window.confirmDelete promise helper)
- Trip delete: trash button in Replay column (server-only via data-deletable on
  trip-list div), DELETE /api/v1/portal/trip/<id>, removes computed trip only
  (raw tracking_points kept)
- Dashcam delete: trash button next to download, DELETE /api/v1/portal/dashcam/<id>,
  removes from DB + disk (best-effort file removal)
- history.js: delete button gated on data-deletable='1' attribute; click handler
  intercepts before replay logic
- db.py: delete_trip(), delete_dashcam_file() helpers

Co-authored-by: Copilot <[email protected]>

server/app.py

@@ -559,6 +559,36 @@ def recompute_trips():
     return jsonify(status="ok", trips_computed=n)
 
 
+@app.delete("/api/v1/portal/trip/<int:trip_id>")
+@require_login
+def portal_delete_trip(trip_id):
+    device_id = _portal_device_id()
+    if device_id is None:
+        return jsonify(error="device not configured"), 404
+    deleted = db.delete_trip(device_id, trip_id)
+    if not deleted:
+        return jsonify(error="trip not found"), 404
+    return jsonify(status="ok")
+
+
+@app.delete("/api/v1/portal/dashcam/<int:file_id>")
+@require_login
+def portal_delete_dashcam(file_id):
+    device_id = _portal_device_id()
+    if device_id is None:
+        return jsonify(error="device not configured"), 404
+    storage_path = db.delete_dashcam_file(device_id, file_id)
+    if storage_path is None:
+        return jsonify(error="file not found"), 404
+    # Remove from disk (best-effort — don't fail if file is already gone)
+    try:
+        if os.path.isfile(storage_path):
+            os.remove(storage_path)
+    except OSError:
+        pass
+    return jsonify(status="ok")
+
+
 @app.get("/api/trips")
 @require_login
 def portal_trips_compat():