chore: import upstream snapshot with attribution

examples/stories/pagination/client.py

@@ -0,0 +1,27 @@
+"""Walk every page of resources/list by hand until next_cursor is absent."""
+
+from mcp.client import Client
+from stories._harness import Target, run_client
+
+
+async def main(target: Target, *, mode: str = "auto") -> None:
+    async with Client(target, mode=mode) as client:
+        names: list[str] = []
+        cursor: str | None = None
+        pages_fetched = 0
+        while True:
+            page = await client.list_resources(cursor=cursor)
+            pages_fetched += 1
+            assert pages_fetched <= 6, "server kept returning next_cursor — runaway guard"
+            names.extend(r.name for r in page.resources)
+            if page.next_cursor is None:  # terminate on absent, NOT on falsy: "" is a valid cursor
+                break
+            cursor = page.next_cursor
+
+        assert names == ["alpha", "beta", "gamma", "delta", "epsilon", "zeta"], names
+        # server_lowlevel.py emits 3 pages of 2; server.py (MCPServer's flat registry) emits 1.
+        assert pages_fetched in (1, 3), pages_fetched
+
+
+if __name__ == "__main__":
+    run_client(main)