Fix image export in container and skip already-local URLs

Mount frontend/public into the api container so the export can write
badge/sprite images. Skip re-downloading URLs that are already local
paths from a previous export.

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

backend/src/app/seeds/run.py

@@ -425,6 +425,14 @@ def _download_image(
 
     Returns the local path (relative to frontend/public).
     """
+    # Already a local path — check the file exists, otherwise re-derive the path
+    if url.startswith("/"):
+        local = FRONTEND_PUBLIC / url.lstrip("/")
+        if local.exists():
+            return url
+        # File missing — can't re-download without the original URL, keep as-is
+        return url
+
     url_ext = url.rsplit(".", 1)[-1].split("?")[0].lower()
     if url_ext in ("png", "jpg", "jpeg", "gif", "webp", "svg"):
         ext = f".{url_ext}"

docker-compose.yml

@@ -8,6 +8,7 @@ services:
     volumes:
       - ./backend/src:/app/src:cached
       - ./backend/alembic.ini:/app/alembic.ini:cached
+      - ./frontend/public:/frontend/public
     environment:
       - DEBUG=true
       - DATABASE_URL=postgresql://postgres:postgres@db:5432/nuzlocke