[Feature][Windows] Enable the static XPU Triton launcher (zebin kernel format + StaticXpuLauncher) on Windows #6167

Feature: make Inductor's static Triton launcher for XPU work on Windows, so torch._C._StaticXpuLauncher is available and CachingAutotuner.can_statically_launch succeeds for XPU kernels.

Motivation: today it is unavailable on Windows for two reasons:

1. Root dependency: the static launcher requires Triton to compile kernels to zebin, which depends on ocloc. Windows does not have ocloc installed by default.
2. torch/_inductor/utils.py:496: XPU_KERNEL_FORMAT = "spv" if _IS_WINDOWS else env("zebin"). With spv, can_statically_launch (runtime/triton_heuristics.py:~3123) raises CannotStaticallyLaunchKernel ("Static XPU ... does not support SPIR-V").
3. torch/csrc/Module.cpp:~2631 guards StaticXpuLauncher_init with #if defined(USE_XPU) && !defined(_WIN32) (added in pytorch #168952), so even a zebin Windows build has no C++ launcher (hasattr(torch._C, "_StaticXpuLauncher") is False).

Kernels silently fall back to TritonCompileResult, which has no recheck_autotune_cache. Consequences:

• inductor/test_codecache.py::TestAutotuneCache::test_autotune_cache_warm_start fails on Windows (release/2.15, BMG): _GlobalItemStats(num_put=2, num_get_hit=0, num_get_miss=2) != Stats(num_put=2, num_get_hit=2, num_get_miss=2) (reproduced 2/2, [release/2.15] UT inductor\test_codecache.py::TestAutotuneCache::test_autotune_cache_warm_start AssertionError: Object comparison failed #5602).
• test/inductor/test_static_triton_launcher.py is not run on XPU-Windows (upstream: # TODO: Enable test on XPU windows once supported, ~line 1452).
• Windows users miss the static-launcher benefits i.e. no Triton compile/import on warm start, lower launch overhead.

Pitch / proposed scope:

1. Ship ocloc for Windows as a pip wheel (like intel-sycl-rt) and make Triton-XPU find it.
2. Make Level Zero native-binary (zebin) generation and loading work with Triton-XPU on Windows.
3. Remove the !_WIN32 guard on StaticXpuLauncher_init; fix Windows build issues.
4. Enable test_static_triton_launcher.py on XPU-Windows and confirm test_autotune_cache_warm_start passes.