[INFRA] Import NVIDIA/CCCL upstream as optimization reference library

CCCL (CUDA C++ Core Libraries) provides:
- CUB: device/block/warp-level GPU primitives (reduce, scan, sort, topk)
- Thrust: high-level parallel algorithms (transform_reduce, sort, scan)
- libcudacxx: CUDA C++ standard library (atomics, barriers, memory)
- cudax: experimental features (memory resources, allocators)
- Tuning policies: per-SM hardware-specific algorithm parameters

Competition optimization vectors mapped to CCCL:
- Output TPS (83% weight): warp_reduce, block_reduce, device_topk
- Input TPS (14% weight): device_scan, block_load, prefetch
- Cache TPS (3% weight): prefix caching strategy patterns
- Memory (0.9 util): pooled/cached/buddy allocators

Source: https://github.com/NVIDIA/cccl (shallow clone, HEAD only)
License: Apache-2.0

cccl_upstream/cudax/include/cuda/experimental/places.cuh

@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of CUDASTF in CUDA C++ Core Libraries,
+// under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+// SPDX-FileCopyrightText: Copyright (c) 2022-2026 NVIDIA CORPORATION & AFFILIATES.
+//
+//===----------------------------------------------------------------------===//
+
+/** @file
+ *
+ * @brief Main include file for the standalone CUDA places library.
+ *
+ * Provides data_place, exec_place, stream_pool, green context support,
+ * place partitioning utilities, and partition strategies (`cyclic_shape`,
+ * `cyclic_partition`, `blocked_partition`, `tiled_partition`) without pulling
+ * in the full CUDASTF task-graph framework.
+ */
+
+#pragma once
+
+#include <cuda/experimental/__places/cute_partition.cuh>
+#include <cuda/experimental/__places/exec/cuda_context.cuh>
+#include <cuda/experimental/__places/exec/cuda_stream.cuh>
+#include <cuda/experimental/__places/exec/green_context.cuh>
+#include <cuda/experimental/__places/exec/green_ctx_view.cuh>
+#include <cuda/experimental/__places/localized_array.cuh>
+#include <cuda/experimental/__places/machine.cuh>
+#include <cuda/experimental/__places/partitions/blocked_partition.cuh>
+#include <cuda/experimental/__places/partitions/cyclic_shape.cuh>
+#include <cuda/experimental/__places/partitions/tiled_partition.cuh>
+#include <cuda/experimental/__places/place_partition.cuh>
+#include <cuda/experimental/__places/places.cuh>
+#include <cuda/experimental/__places/stream_pool.cuh>