feat(assets): add helpers package for chroma lexer map generation (#781)

- Add `packages/helpers` with CLI dispatcher pattern for code generation
- Add `chroma-lexers` helper that fetches lexer definitions from alecthomas/chroma
- Rename `$code-type-map` to `$chroma-lexers`, `_code-type.scss` to `_chroma-lexers.scss`
- Fix `fi-var` and `set-fi-var` to preserve quotes for string fallbacks
- Add `capitalize` utility to `packages/shared`
- Replace `console.*` with `consola` in packages
- Add `pnpm gen:lexers` script and CI workflow for auto-regeneration
- Update CLAUDE.md and CONTRIBUTING.md

package.json

@@ -41,6 +41,7 @@
     "typecheck": "tsc --noEmit",
     "version": "pnpm -F versioning start prod",
     "changelog": "auto-changelog-plus --starting-date 2021-12-18",
+    "gen:lexers": "pnpm -F helpers start chroma-lexers",
     "prepare": "simple-git-hooks"
   },
   "devDependencies": {