Add game_id FK to BossBattle for version-exclusive bosses

Version-exclusive bosses (e.g., Bea in Sword, Allister in Shield) were
using the section field to indicate which game they belong to. This adds
a proper game_id foreign key so the API can filter bosses per game,
keeping section free for visual grouping like "Main Story".

- Alembic migration adds nullable game_id column with FK and index
- API list_bosses filters by game_id unless ?all=true is passed
- Seed data updated to use game_slug instead of section overloading
- Admin form adds "Game (version exclusive)" dropdown
- Export endpoints include game_slug for exclusive bosses

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

backend/src/app/seeds/data/black-bosses.json

@@ -107,8 +107,9 @@
     "order": 8,
     "after_route_name": null,
     "location": "Opelucid Gym",
-    "section": "Black",
+    "section": null,
     "sprite_url": "/boss-sprites/black/drayden.png",
+    "game_slug": "black",
     "pokemon": []
   },
   {
@@ -121,8 +122,9 @@
     "order": 9,
     "after_route_name": null,
     "location": "Opelucid Gym",
-    "section": "White",
+    "section": null,
     "sprite_url": "/boss-sprites/black/iris.png",
+    "game_slug": "white",
     "pokemon": []
   },
   {

backend/src/app/seeds/data/sword-bosses.json

@@ -51,8 +51,9 @@
     "order": 4,
     "after_route_name": null,
     "location": "Stow-on-Side Stadium",
-    "section": "Sword",
+    "section": null,
     "sprite_url": "/boss-sprites/sword/bea.png",
+    "game_slug": "sword",
     "pokemon": []
   },
   {
@@ -65,8 +66,9 @@
     "order": 5,
     "after_route_name": null,
     "location": "Stow-on-Side Stadium",
-    "section": "Shield",
+    "section": null,
     "sprite_url": "/boss-sprites/sword/allister.png",
+    "game_slug": "shield",
     "pokemon": []
   },
   {
@@ -93,8 +95,9 @@
     "order": 7,
     "after_route_name": null,
     "location": "Circhester Stadium",
-    "section": "Sword",
+    "section": null,
     "sprite_url": "/boss-sprites/sword/gordie.png",
+    "game_slug": "sword",
     "pokemon": []
   },
   {
@@ -107,8 +110,9 @@
     "order": 8,
     "after_route_name": null,
     "location": "Circhester Stadium",
-    "section": "Shield",
+    "section": null,
     "sprite_url": "/boss-sprites/sword/melony.png",
+    "game_slug": "shield",
     "pokemon": []
   },
   {

backend/src/app/seeds/loader.py

@@ -239,6 +239,7 @@ async def upsert_bosses(
     bosses: list[dict],
     dex_to_id: dict[int, int],
     route_name_to_id: dict[str, int] | None = None,
+    slug_to_game_id: dict[str, int] | None = None,
 ) -> int:
     """Upsert boss battles for a version group, return count of bosses upserted."""
     count = 0
@@ -253,6 +254,16 @@ async def upsert_bosses(
                     f"  Warning: route '{after_route_name}' not found for boss '{boss['name']}'"
                 )
 
+        # Resolve game_slug to game_id
+        game_id = None
+        game_slug = boss.get("game_slug")
+        if game_slug and slug_to_game_id:
+            game_id = slug_to_game_id.get(game_slug)
+            if game_id is None:
+                print(
+                    f"  Warning: game '{game_slug}' not found for boss '{boss['name']}'"
+                )
+
         # Upsert the boss battle on (version_group_id, order) conflict
         stmt = (
             insert(BossBattle)
@@ -269,6 +280,7 @@ async def upsert_bosses(
                 location=boss["location"],
                 section=boss.get("section"),
                 sprite_url=boss.get("sprite_url"),
+                game_id=game_id,
             )
             .on_conflict_do_update(
                 constraint="uq_boss_battles_version_group_order",
@@ -283,6 +295,7 @@ async def upsert_bosses(
                     "location": boss["location"],
                     "section": boss.get("section"),
                     "sprite_url": boss.get("sprite_url"),
+                    "game_id": game_id,
                 },
             )
             .returning(BossBattle.id)

backend/src/app/seeds/run.py

@@ -160,7 +160,7 @@ async def seed():
 
             route_name_to_id = route_maps_by_vg.get(vg_id, {})
             boss_count = await upsert_bosses(
-                session, vg_id, bosses_data, dex_to_id, route_name_to_id
+                session, vg_id, bosses_data, dex_to_id, route_name_to_id, slug_to_id
             )
             total_bosses += boss_count
             print(f"  {vg_slug}: {boss_count} bosses")
@@ -491,6 +491,7 @@ async def _export_bosses(session: AsyncSession, vg_data: dict):
             .options(
                 selectinload(BossBattle.pokemon).selectinload(BossPokemon.pokemon),
                 selectinload(BossBattle.after_route),
+                selectinload(BossBattle.game),
             )
             .order_by(BossBattle.order)
         )
@@ -525,30 +526,31 @@ async def _export_bosses(session: AsyncSession, vg_data: dict):
                     downloaded_sprites,
                 )
 
-            data.append(
-                {
-                    "name": b.name,
-                    "boss_type": b.boss_type,
-                    "specialty_type": b.specialty_type,
-                    "badge_name": b.badge_name,
-                    "badge_image_url": badge_image_url,
-                    "level_cap": b.level_cap,
-                    "order": b.order,
-                    "after_route_name": b.after_route.name if b.after_route else None,
-                    "location": b.location,
-                    "section": b.section,
-                    "sprite_url": sprite_url,
-                    "pokemon": [
-                        {
-                            "pokeapi_id": bp.pokemon.pokeapi_id,
-                            "pokemon_name": bp.pokemon.name,
-                            "level": bp.level,
-                            "order": bp.order,
-                        }
-                        for bp in sorted(b.pokemon, key=lambda p: p.order)
-                    ],
-                }
-            )
+            boss_dict: dict = {
+                "name": b.name,
+                "boss_type": b.boss_type,
+                "specialty_type": b.specialty_type,
+                "badge_name": b.badge_name,
+                "badge_image_url": badge_image_url,
+                "level_cap": b.level_cap,
+                "order": b.order,
+                "after_route_name": b.after_route.name if b.after_route else None,
+                "location": b.location,
+                "section": b.section,
+                "sprite_url": sprite_url,
+                "pokemon": [
+                    {
+                        "pokeapi_id": bp.pokemon.pokeapi_id,
+                        "pokemon_name": bp.pokemon.name,
+                        "level": bp.level,
+                        "order": bp.order,
+                    }
+                    for bp in sorted(b.pokemon, key=lambda p: p.order)
+                ],
+            }
+            if b.game_id:
+                boss_dict["game_slug"] = b.game.slug
+            data.append(boss_dict)
 
         _write_json(f"{first_game_slug}-bosses.json", data)
         exported += 1