Add HeaderDescriptorSpec for mathdx

Author: rwgk

cuda_pathfinder/cuda/pathfinder/_headers/header_descriptor_catalog.py

@@ -153,6 +153,14 @@ class HeaderDescriptorSpec:
         conda_targets_layout=False,
         use_ctk_root_canary=False,
     ),
+    HeaderDescriptorSpec(
+        name="mathdx",
+        packaged_with="other",
+        header_basename="libmathdx.h",
+        site_packages_dirs=("nvidia/cu13/include", "nvidia/cu12/include"),
+        conda_targets_layout=False,
+        use_ctk_root_canary=False,
+    ),
     HeaderDescriptorSpec(
         name="nvshmem",
         packaged_with="other",

cuda_pathfinder/tests/test_find_nvidia_headers.py

@@ -42,6 +42,7 @@
 NON_CTK_IMPORTLIB_METADATA_DISTRIBUTIONS_NAMES = {
     "cusparseLt": r"^nvidia-cusparselt-.*$",
     "cutensor": r"^cutensor-.*$",
+    "mathdx": r"^nvidia-libmathdx-.*$",
     "nvshmem": r"^nvidia-nvshmem-.*$",
 }