- Add KVStore, MessageStore, StoredMessage, MessageFilter interfaces to types.ts
- Add InMemoryKVStore and InMemoryMessageStore default implementations
- Add RedisStore implementing KVStore with Hash per entry, structural client typing
- Refactor MessageBus and SharedMemory to accept injected stores
- Wire TeamConfig.store and TeamConfig.messageStore into Team
- Add redis as optional peer dependency
- Update AGENTS.md with pluggable storage notes
- Add design doc and implementation plan