help-beta: Add MDX formatting to the linter.

tools/format-mdx

@@ -0,0 +1,9 @@
+#!/usr/bin/env python3
+
+import subprocess
+
+subprocess.check_call(
+    ["/usr/local/bin/corepack", "pnpm", "run", "format"],
+    cwd="starlight_help",
+    stdout=subprocess.DEVNULL,
+)

tools/lint

@@ -64,6 +64,7 @@ def run() -> None:
                 "hbs",
                 "html",
                 "js",
+                "mdx",
                 "mjs",
                 "mts",
                 "svg",
@@ -219,6 +220,12 @@ def run() -> None:
         ["tools/check-thirdparty"],
         description="Check docs/THIRDPARTY copyright file syntax",
     )
+    linter_config.external_linter(
+        "format-mdx",
+        ["tools/format-mdx"],
+        ["mdx"],
+        description="Lint and format MDX files",
+    )
 
     @linter_config.lint
     def custom_py() -> int: