chore: dev/prod Docker compose separation with safety docs

- Add docker-compose.override.yml exposing db/redis ports for local dev
- Remove override from .gitignore so all devs get port mappings
- Use explicit -f in deploy.sh to skip override in production
- Document production safety rule: always use -f on the server

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

.gitignore

@@ -156,9 +156,7 @@ uploads/
 __pypackages__/
 
 # Docker
-docker-compose.override.yml
 .dockerignore.local
-*.override.yml
 
 # Deployment & Security
 .build-info