Five follow-ups to topic mode based on integration audit:
1. ON DELETE CASCADE on telegram_dm_topic_bindings.session_id. Session
pruning (manual /delete, auto-cleanup, any future prune job) would
have thrown 'FOREIGN KEY constraint failed' for sessions bound to a
topic. Migration bumped to v2, rebuilds the bindings table in place
if FK lacks CASCADE. Idempotent; only runs once per DB.
2. Never auto-rename operator-declared topics. If an operator has
extra.dm_topics configured AND a user runs /topic, messages in those
pre-declared topics would previously trigger auto-rename and silently
mutate operator config. _rename_telegram_topic_for_session_title now
early-returns when _get_dm_topic_info returns a dict for this
(chat_id, thread_id). Uses class-based lookup (not hasattr) so
MagicMock test fixtures don't accidentally trip the guard.
3. General topic handling. Telegram's General (pinned top) topic in a
forum-enabled private chat may send messages with message_thread_id=1
or omit thread_id entirely depending on client. Both are now treated
as the root lobby, not a topic lane. Prevents users from
accidentally burning a session on the General topic.
4. Debounce the root-lobby reminder. 30-second cooldown per chat so a
user who forgets topic mode is enabled and types ten messages in the
root gets one reminder, not ten. Explicit command replies
(/new-in-lobby, /topic <session-id>) still land every time.
5. Docs: added under-the-hood invariants for the above, plus a
Downgrade section explaining that rolling back to a pre-/topic
Hermes build leaves the DB tables orphaned but harmless — DMs just
revert to native per-thread isolation.
Tests:
- test_operator_declared_topic_is_not_auto_renamed
- test_general_topic_is_treated_as_root_lobby
- test_lobby_reminder_is_debounced_per_chat
- test_binding_survives_session_deletion_via_cascade
- test_migration_rebuilds_v1_binding_table_with_cascade_fk
Validated: 4803/4804 tests pass (tests/gateway/ + tests/test_hermes_state.py).
Sole failure is a pre-existing test_teams::test_send_typing flake
unrelated to this PR.
1381c89e56