fix: scan episodes synchronously and disable test mode rate limiting

- Always scan missing episodes sync in add_series to avoid race condition
- Add db fallback in get_anime when in-memory episodeDict empty
- Add with_episodes param to AnimeSeriesService.get_by_key
- Disable auth rate limiting and lockout in test mode (ANIWORLD_TESTING=1)
- Simplify responsive.robot tests: fix setup, remove fragile width checks

src/server/database/service.py

@@ -140,7 +140,11 @@ class AnimeSeriesService:
         return result.scalar_one_or_none()
     
     @staticmethod
-    async def get_by_key(db: AsyncSession, key: str) -> Optional[AnimeSeries]:
+    async def get_by_key(
+        db: AsyncSession,
+        key: str,
+        with_episodes: bool = False,
+    ) -> Optional[AnimeSeries]:
         """Get anime series by provider key.
         
         This is the PRIMARY lookup method for series identification.
@@ -150,6 +154,7 @@ class AnimeSeriesService:
         Args:
             db: Database session
             key: Unique provider key (e.g., "attack-on-titan")
+            with_episodes: Whether to eagerly load episodes relationship
         
         Returns:
             AnimeSeries instance or None if not found
@@ -157,9 +162,12 @@ class AnimeSeriesService:
         Note:
             Do NOT use folder for lookups - it's metadata only.
         """
-        result = await db.execute(
-            select(AnimeSeries).where(AnimeSeries.key == key)
-        )
+        query = select(AnimeSeries).where(AnimeSeries.key == key)
+        
+        if with_episodes:
+            query = query.options(selectinload(AnimeSeries.episodes))
+        
+        result = await db.execute(query)
         return result.scalar_one_or_none()
 
     @staticmethod