Update build system: skip pyclibrary for nvrtc, fix cynvrtc source path

- Remove nvrtc from _REQUIRED_HEADERS (no pyclibrary parsing needed;
  nvrtc .pyx/.pxd files are now pre-generated by cybind)
- Update sources_list: cynvrtc.pyx moved from _bindings/ to bindings/
- _rename_architecture_specific_files already handles
  _internal/nvrtc_linux.pyx -> _internal/nvrtc.pyx

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: leofang

cuda_bindings/build_hooks.py

@@ -94,9 +94,7 @@ def _get_cuda_path() -> str:
         "driver_functions.h",
         "cuda_profiler_api.h",
     ],
-    "nvrtc": [
-        "nvrtc.h",
-    ],
+    # nvrtc: headers no longer parsed at build time (pre-generated by cybind).
     # During compilation, Cython will reference C headers that are not
     # explicitly parsed above. These are the known dependencies:
     #
@@ -423,7 +421,7 @@ def _cleanup_dst_files():
     sources_list = [
         # private
         (["cuda/bindings/_bindings/cydriver.pyx", "cuda/bindings/_bindings/loader.cpp"], None),
-        (["cuda/bindings/_bindings/cynvrtc.pyx"], None),
+        (["cuda/bindings/cynvrtc.pyx"], None),
         (["cuda/bindings/_bindings/cyruntime.pyx"], static_runtime_libraries),
         (["cuda/bindings/_bindings/cyruntime_ptds.pyx"], static_runtime_libraries),
         # utils