p0: harden realtime reconciliation and revoke-all token invalidation

docs/api-reference.md

@@ -508,7 +508,8 @@ Response: `204`
 ### DELETE `/api/v1/auth/sessions`
 
 Auth required.  
-Response: `204`
+Response: `204`  
+Behavior: revokes all refresh sessions and invalidates all access tokens issued before this request.
 
 ### POST `/api/v1/auth/2fa/setup`
 

docs/realtime.md

@@ -236,5 +236,6 @@ Validation/runtime error during WS processing:
 - Send periodic `ping` and expect `pong`.
 - Reconnect with exponential backoff.
 - On `chat_updated`, refresh chat metadata via REST (`GET /api/v1/chats` or `GET /api/v1/chats/{chat_id}`).
+- On reconnect/visibility restore, reconcile state by reloading already-opened chats/messages via REST
+  to recover missed `message_deleted`/delivery updates after transient disconnects or backend restarts.
 - Use REST message history endpoints for pagination; WS is realtime transport, not history source.
-