feat(backend): feed of deleted and edited messages with bulk deletions grouped and a shared seen marker

backend/src/utils/read/models.py

@@ -212,6 +212,48 @@ class MessageVersionView(BaseModel):
     text: str | None
 
 
+class FeedChat(BaseModel):
+    chat_id: int
+    title: str | None
+    kind: str
+    has_avatar: bool
+
+
+class FeedItem(BaseModel):
+    id: int
+    kind: str
+    at: datetime
+    since: datetime
+    message_count: int
+    chat: FeedChat
+    message: MessageView | None
+    sender_id: int | None
+    sender_name: str | None
+    outgoing: bool
+    before: str | None = None
+    after: str | None = None
+    has_before: bool = False
+    edit_date: datetime | None = None
+
+
+class FeedPage(BaseModel):
+    items: list[FeedItem]
+    next_cursor: str | None
+
+
+class FeedUnseen(BaseModel):
+    count: int
+    deleted: int
+    edited: int
+    seen_at: datetime | None
+    latest: FeedItem | None
+
+
+class FeedMessagesPage(BaseModel):
+    messages: list[MessageView]
+    next_cursor: str | None
+
+
 class MediaView(BaseModel):
     id: int
     account_id: int