feat: add is_chat field to board memory and task_id to approvals, update pagination and response models

backend/app/schemas/pagination.py

@@ -0,0 +1,21 @@
+from __future__ import annotations
+
+from typing import TypeVar
+
+from fastapi import Query
+from fastapi_pagination.customization import CustomizedPage, UseParamsFields
+from fastapi_pagination.limit_offset import LimitOffsetPage
+
+T = TypeVar("T")
+
+
+# Project-wide default pagination response model.
+# - Keep `limit` / `offset` naming (matches existing API conventions).
+# - Cap list endpoints to 200 items per request (matches prior route-level constraints).
+DefaultLimitOffsetPage = CustomizedPage[
+    LimitOffsetPage[T],
+    UseParamsFields(
+        limit=Query(200, ge=1, le=200),
+        offset=Query(0, ge=0),
+    ),
+]