When the Synology Chat plugin restarts (auto-restart or health monitor),
startAccount is called again without calling the previous stop(). The
HTTP route is still registered, so registerPluginHttpRoute returns a
no-op unregister function and logs "already registered". This triggers
another restart, creating an infinite loop.
Store the unregister function at module level keyed by account+path.
Before registering, check for and call any stale unregister from the
previous start cycle, ensuring a clean slate for route registration.
Fixes#24894
Co-authored-by: Cursor <cursoragent@cursor.com>
f5cab29ec7