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/modules/db.py

@@ -348,6 +348,27 @@ def get_dashcam_file(device_id, file_id):
     return {"id": r[0], "relative_path": r[1], "size_bytes": r[2], "uploaded_at": r[3].isoformat(), "storage_path": r[4]}
 
 
+def delete_trip(device_id, trip_id):
+    """Delete a computed trip record. Raw tracking_points are NOT removed."""
+    with get_cursor(commit=True) as cur:
+        cur.execute(
+            "DELETE FROM trips WHERE id = %s AND device_id = %s RETURNING id",
+            (trip_id, device_id),
+        )
+        return cur.fetchone() is not None
+
+
+def delete_dashcam_file(device_id, file_id):
+    """Delete dashcam file from DB and disk. Returns storage_path if deleted, None if not found."""
+    with get_cursor(commit=True) as cur:
+        cur.execute(
+            "DELETE FROM dashcam_files WHERE id = %s AND device_id = %s RETURNING storage_path",
+            (file_id, device_id),
+        )
+        row = cur.fetchone()
+    return row[0] if row else None
+
+
 def get_overview_stats(device_id):
     with get_cursor() as cur:
         cur.execute(