feat(backend): presence stats count time online from sessions in the browser time zone, capture uptime marks hours without data, presence reaches every stream of the account, message volume keeps empty days

backend/src/api/realtime.py

@@ -59,16 +59,12 @@ class EventHub:
             return
         account_id = event.get("account_id")
         chat_id = event.get("chat_id")
-        scoped = event.get("kind") == "presence"
+        account_wide = event.get("kind") == "presence"
         targets = [
             sub
             for sub in self._subscribers
             if sub.account_id == account_id
-            and (
-                sub.chat_id == chat_id
-                if scoped
-                else sub.chat_id is None or sub.chat_id == chat_id
-            )
+            and (account_wide or sub.chat_id is None or sub.chat_id == chat_id)
         ]
         if not targets:
             return