feat(backend): read time of my messages from the archive, exact dates and group readers asked from telegram on demand

backend/src/utils/read/chats.py

@@ -10,7 +10,7 @@ from utils.read.models import (
     MessageView,
     Page,
 )
-from utils.read.read_receipts import read_up_to
+from utils.read.read_receipts import read_times, read_up_to
 
 _MESSAGE_COLS = (
     "chat_id, message_id, date, sender_id, text, has_media, is_self_destruct, "
@@ -285,12 +285,18 @@ async def _apply_read_status(
     self_id = await self_user_id(pool, account_id)
     if self_id is None:
         return
-    marker = await read_up_to(pool, account_id, chat_id)
-    if marker is None:
+    own = [view for view in views if view.sender_id == self_id]
+    if not own:
         return
-    for view in views:
-        if view.sender_id == self_id and view.message_id <= marker:
-            view.read = True
+    marker = await read_up_to(pool, account_id, chat_id)
+    times = await read_times(
+        pool, account_id, chat_id, [(view.message_id, view.date) for view in own]
+    )
+    for view in own:
+        view.read_at = times.get(view.message_id)
+        view.read = view.read_at is not None or (
+            marker is not None and view.message_id <= marker
+        )
 
 
 def _build_album(