build(lint): enforce Prettier formatting for SCSS in CI and npm run lint

Problem

There is an asymmetry between pre-commit linting and CI verification for SCSS files:

1. Pre-commit hook formats SCSS: In package.json, lint-staged runs Prettier across *.{json,ts,html,scss,css}.
2. CI and npm run lint ignore SCSS:
   • package.json: "lint": "prettier --check \"utils/**/*.ts\" \"functions/**/*.ts\" \"frontend/**/*.ts\" ..."
   • .github/workflows/ci.yaml: npx prettier --check "**/*.ts"

Impact & Evidence

Because CI never enforces SCSS formatting, formatting drift goes unnoticed in main. An audit reveals that 22 SCSS files currently fail Prettier's check (mostly using double quotes rather than the configured 'singleQuote': true in .prettierrc.json).

When a contributor subsequently touches any of those 22 files (as happened in PR #1230 with info_view.scss), Husky's pre-commit hook auto-formats the file, introducing noisy, incidental quote-swapping diffs on untouched lines.

Proposed Mitigation

1. One-time formatting migration:
   Run npx prettier --write "**/*.scss" across the monorepo in a dedicated cleanup PR to format the 22 drifting files.
2. Enforce in package.json:
   Update the root lint script to include frontend/src/**/*.scss.
3. Enforce in CI:
   Update the Check format step in .github/workflows/ci.yaml to include SCSS:

   - name: Check format
     run: |
       npx prettier --check "**/*.ts" "**/*.scss"
       npx eslint --quiet "**/*.ts"
   

Acceptance Criteria

• All SCSS files formatted per .prettierrc.json.
• npm run lint checks SCSS files locally.
• GitHub Actions CI rejects PRs with unformatted SCSS files.

Start with the root package.json lint script, .github/workflows/ci.yaml Check format step, and .prettierrc.json to understand the existing patterns. Run the documented Prettier check and inspect the SCSS files it reports, including the 22-file formatting drift. Done means all SCSS follows the configured format and both local linting and CI verify it.