added frontend for social + feed partiali working

backend/vontor_cz/pagination.py

@@ -0,0 +1,31 @@
+"""Shared pagination classes.
+
+`CreatedCursorPagination` is the canonical choice for infinite-scroll feeds
+(posts feed, chat message history). Cursor pagination keeps a stable view of
+results even when new items are created at the head, which page/offset
+pagination does not.
+"""
+
+from rest_framework.pagination import CursorPagination
+
+
+class CreatedCursorPagination(CursorPagination):
+    """Cursor pagination ordered by `-created_at` (newest first)."""
+    page_size = 20
+    ordering = '-created_at'
+    cursor_query_param = 'cursor'
+    page_size_query_param = 'page_size'
+    max_page_size = 100
+
+
+class CreatedAscCursorPagination(CursorPagination):
+    """Cursor pagination ordered by `created_at` (oldest first).
+
+    Used for chat history scroll-back where messages are displayed oldest -> newest
+    and pagination walks backwards in time from the most recent.
+    """
+    page_size = 30
+    ordering = '-created_at'  # backend orders newest-first; client reverses for display
+    cursor_query_param = 'cursor'
+    page_size_query_param = 'page_size'
+    max_page_size = 100