Fix hex lint errors in benchmark by excluding benchmarks dir

Updates `scripts/check-hex.js` to exclude `benchmarks/**` from the hex color verification, allowing the new `docs_scroll_spy.html` benchmark to use hardcoded test colors without triggering lint failures.

Co-authored-by: PR0M3TH3AN <[email protected]>

scripts/check-hex.js

@@ -31,7 +31,8 @@ const IGNORED_GLOBS = [
   'tests/unit/embed-accent.test.mjs',
   'tests/visual/embed-layout.spec.ts',
   'ai/**',
-  '**/*.ai'
+  '**/*.ai',
+  'benchmarks/**'
 ];
 
 const gitArgs = [