feat: add auth system, boss pokemon details, moves/abilities API, and run ownership

Add user authentication with login/signup/protected routes, boss pokemon
detail fields and result team tracking, moves and abilities selector
components and API, run ownership and visibility controls, and various
UI improvements across encounters, run list, and journal pages.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/src/app/core/config.py

@@ -17,5 +17,10 @@ class Settings(BaseSettings):
     # Database settings
     database_url: str = "postgresql+asyncpg://postgres:postgres@localhost:5432/nuzlocke"
 
+    # Supabase Auth
+    supabase_url: str | None = None
+    supabase_anon_key: str | None = None
+    supabase_jwt_secret: str | None = None
+
 
 settings = Settings()