Task 4: stale room blocking + agent_id binding
- MatrixBot._check_agent_routing: blocks normal messages when user has no
selected agent or room is bound to a different agent
- agent_routing_enabled flag on MatrixRuntime activates the check only
in real multi-agent mode (RoutedPlatformClient)
- make_handle_new_chat now writes agent_id into new room metadata when
user already has a selected agent
Task 5: durable restart state tests
- test_restart_persistence.py proves selected_agent_id, room agent_id,
platform_chat_id, and the sequence counter all survive SQLiteStore
close/reopen; also covers clean startup with no prior state
- harden Matrix onboarding/chat lifecycle after manual QA
- refresh README and Matrix docs to match current behavior
- add local ignores for runtime artifacts and include current planning/report docs
Closes#7Closes#9Closes#14
- register archive and rename as client-aware closure handlers
- rename matrix rooms via stored surface_ref when a client is available
- keep archive scoped to core chat state for phase 1
- create new chat rooms inside the user's space
- store space-aware room metadata with next_chat_id
- handle room creation failures with user-facing messages
