Address PR #20 feedback:

- Removed PersonalStorage (redundant - RoomStorage handles both via room_id)
- Added ensure_room() and ensure_tracking() methods for explicit creation
- Added @runtime_checkable to Protocols for isinstance checks
- Added tests/test_ports.py with 11 unit tests for storage protocols

core/__init__.py

@@ -8,7 +8,6 @@ from core.models import (
 )
 from core.ports import (
     RoomStorage,
-    PersonalStorage,
     TrackingStorage,
 )
 
@@ -18,6 +17,5 @@ __all__ = [
     "RoomData",
     "TrackingData",
     "RoomStorage",
-    "PersonalStorage",
     "TrackingStorage",
 ]