Add after_route_name to boss battle export/seed pipeline

Exports now include after_route_name (resolved from the route FK),
and the seed loader resolves it back to an ID on import. Also adds
a draft bean for displaying encounter-less locations.

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

backend/src/app/seeds/run.py

@@ -68,6 +68,7 @@ async def seed():
             # 4. Per version group: upsert routes once, then encounters per game
             total_routes = 0
             total_encounters = 0
+            route_maps_by_vg: dict[int, dict[str, int]] = {}
 
             for vg_slug, vg_info in vg_data.items():
                 vg_id = vg_slug_to_id[vg_slug]
@@ -87,6 +88,7 @@ async def seed():
 
                 # Upsert routes once per version group
                 route_map = await upsert_routes(session, vg_id, routes_data)
+                route_maps_by_vg[vg_id] = route_map
                 total_routes += len(route_map)
                 print(f"  {vg_slug}: {len(route_map)} routes")
 
@@ -147,7 +149,8 @@ async def seed():
                 if not bosses_data:
                     continue
 
-                boss_count = await upsert_bosses(session, vg_id, bosses_data, dex_to_id)
+                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)
                 total_bosses += boss_count
                 print(f"  {vg_slug}: {boss_count} bosses")
 
@@ -416,6 +419,7 @@ async def _export_bosses(session: AsyncSession, vg_data: dict):
             .where(BossBattle.version_group_id == vg.id)
             .options(
                 selectinload(BossBattle.pokemon).selectinload(BossPokemon.pokemon),
+                selectinload(BossBattle.after_route),
             )
             .order_by(BossBattle.order)
         )
@@ -434,6 +438,7 @@ async def _export_bosses(session: AsyncSession, vg_data: dict):
                 "badge_image_url": b.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": b.sprite_url,