feat: implement cursor-based pagination across various components and APIs

api/response.py

@@ -9,7 +9,25 @@ def success(data: Any = None, msg: str = "ok", code: int = 0):
 def page(items: list[Any], total: int, page: int, page_size: int):
     """统一分页数据结构。"""
     pages = (total + page_size - 1) // page_size if page_size else 0
-    return {"items": items, "total": total, "page": page, "page_size": page_size, "pages": pages}
+    return {"items": items, "total": total, "page": page, "page_size": page_size, "pages": pages, "pagination_mode": "paged"}
+
+
+def cursor_page(
+    items: list[Any],
+    page_size: int,
+    *,
+    cursor: str | None = None,
+    next_cursor: str | None = None,
+):
+    """无总数游标分页结构。"""
+    return {
+        "items": items,
+        "page_size": page_size,
+        "pagination_mode": "cursor",
+        "cursor": cursor,
+        "next_cursor": next_cursor,
+        "has_next": bool(next_cursor),
+    }
 
 
 def error(msg: str, code: int = 1, data: Optional[Any] = None):