web: Type Tidy (#14647)

* web: Update Sentry types.

* web: Update MDX types.

* web: Format. Remove unused script.

* web: Clean up test types.

* web: Fix label in dark mode.

web/web-test-runner.config.mjs

@@ -1,6 +1,16 @@
-export default {
+/**
+ * @file Web Test Runner configuration.
+ * @see https://modern-web.dev/docs/test-runner/cli-and-configuration/
+ */
+
+/**
+ * @type {import('@web/test-runner').TestRunnerConfig}
+ */
+const config = {
     files: ["dist/**/*.spec.js"],
     nodeResolve: {
         exportConditions: ["browser", "production"],
     },
 };
+
+export default config;