feat: implement user data schema and API endpoints

- Add Alembic migration setup with async configuration
- Create 16 user data models (users, decks, cards, replays, etc.)
- Implement comprehensive API endpoints with JWT auth
- Add replay, card collection, group, network, preferences, and activity log routers
- Include API documentation and migration test plan
- Update Dockerfile to run migrations on startup

backend/app/models/__init__.py

@@ -2,6 +2,12 @@
 from app.models.models import User, DecklistFile, DecklistFolder, Room, RoomGameType, Ban, GameLog, AuditLog
 from app.models.mtg_models import MtgSet, MtgCard
 from app.models.mirror_models import MtgCardMirror, DeckCardLink
+from app.models.user_data import (
+    UserSession, DeckVersion, GameReplay, ReplayPlayer,
+    GameOutcome, UserStatistics, UserCardCollection, CardWishlist,
+    UserGroup, GroupMember, GroupChatMessage, UserNetwork,
+    NetworkMember, UserPreference, UserActivityLog
+)
 
 __all__ = [
     "User",
@@ -16,4 +22,19 @@ __all__ = [
     "MtgCard",
     "MtgCardMirror",
     "DeckCardLink",
+    "UserSession",
+    "DeckVersion",
+    "GameReplay",
+    "ReplayPlayer",
+    "GameOutcome",
+    "UserStatistics",
+    "UserCardCollection",
+    "CardWishlist",
+    "UserGroup",
+    "GroupMember",
+    "GroupChatMessage",
+    "UserNetwork",
+    "NetworkMember",
+    "UserPreference",
+    "UserActivityLog",
 ]