Add race and station management

- races table: name, date, description, is_active
- stations table: ordered checkpoints with GPS per race
- New /api/races and /api/races/{id}/stations endpoints
- Upload now requires race + station selection; uses station GPS
  so images without GPS EXIF are accepted
- passages filtered by active race throughout
- RacePage: create races, manage stations (add/edit/delete checkpoints)
- Navbar shows active race name
- Start and finish stations created automatically per race

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

backend/passage_log.py

@@ -50,6 +50,7 @@ async def _find_active_passage(
 async def log_passage(
     db: aiosqlite.Connection,
     *,
+    race_id: Optional[str] = None,
     profile_id: Optional[str],
     bib_number: Optional[str],
     station: str,
@@ -112,14 +113,14 @@ async def log_passage(
     await db.execute(
         """
         INSERT INTO passages (
-            passage_id, profile_id, bib_number, station,
+            passage_id, race_id, profile_id, bib_number, station,
             timestamp_utc, gps_lat, gps_lon, gps_alt,
             confidence, id_method, source_image,
             needs_review, review_note
-        ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+        ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
         """,
         (
-            passage_id, profile_id, bib_number, station,
+            passage_id, race_id, profile_id, bib_number, station,
             timestamp_utc.isoformat(), gps_lat, gps_lon, gps_alt,
             confidence, id_method, source_image,
             int(needs_review), review_note,
@@ -153,12 +154,16 @@ async def get_passage_images(db: aiosqlite.Connection, passage_id: str) -> list[
 
 async def get_passages(
     db: aiosqlite.Connection,
+    race_id: Optional[str] = None,
     profile_id: Optional[str] = None,
     station: Optional[str] = None,
     needs_review: Optional[bool] = None,
 ) -> list[dict]:
     clauses = []
     params = []
+    if race_id is not None:
+        clauses.append("p.race_id = ?")
+        params.append(race_id)
     if profile_id is not None:
         clauses.append("p.profile_id = ?")
         params.append(profile_id)