feat: migrate from ESLint/Prettier to Biome

- Replace ESLint + Prettier with Biome for faster linting/formatting
- Add biome.json with equivalent rules and formatting config
- Update CI workflow to use 'biome ci' (single command)
- Configure VSCode settings and extensions for Biome
- Setup pre-commit hook with lint-staged using Biome
- Remove debug API routes (test-env, list-sheets)
- Add type-safe error handling with custom ApiError classes
- Improve README: add CI badge, troubleshooting, CI/CD setup
- Update all scripts to use Biome commands
- Move autoprefixer to devDependencies (proper placement)

BREAKING CHANGE: Prettier plugin for Tailwind removed (Biome doesn't support plugins). Class ordering must be manual or use editor extensions.

Author: rafactx

.github/workflows/ci.yml

@@ -11,8 +11,8 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
-  lint-and-type-check:
-    name: Lint & Type Check
+  lint-and-check:
+    name: Lint, Format & Type Check
     runs-on: ubuntu-latest
 
     steps:
@@ -27,19 +27,21 @@ jobs:
       - name: Install dependencies
         run: bun install --frozen-lockfile
 
-      - name: Run ESLint
-        run: bun run lint
-
-      - name: Run TypeScript
-        run: bun run type-check
+      - name: Cache Biome
+        uses: actions/cache@v4
+        with:
+          path: node_modules/.cache/biome
+          key: ${{ runner.os }}-biome-${{ hashFiles('**/biome.json') }}
+          restore-keys: |
+            ${{ runner.os }}-biome-
 
-      - name: Check Prettier formatting
-        run: bun run format:check
+      - name: Run Biome CI
+        run: bun run ci
 
   build:
     name: Build
     runs-on: ubuntu-latest
-    needs: lint-and-type-check
+    needs: lint-and-check
 
     steps:
       - name: Checkout code
@@ -56,10 +58,10 @@ jobs:
       - name: Build application
         run: bun run build
         env:
-          GOOGLE_SHEETS_CLIENT_EMAIL: ${{ secrets.GOOGLE_SHEETS_CLIENT_EMAIL }}
-          GOOGLE_SHEETS_PRIVATE_KEY: ${{ secrets.GOOGLE_SHEETS_PRIVATE_KEY }}
-          GOOGLE_SHEETS_SPREADSHEET_ID: ${{ secrets.GOOGLE_SHEETS_SPREADSHEET_ID }}
-          GOOGLE_SHEETS_SHEET_NAME: ${{ secrets.GOOGLE_SHEETS_SHEET_NAME }}
+          GOOGLE_SHEETS_CLIENT_EMAIL: "ci-test@example.com"
+          GOOGLE_SHEETS_PRIVATE_KEY: "-----BEGIN PRIVATE KEY-----\nMOCK_KEY_FOR_CI_BUILD_ONLY\n-----END PRIVATE KEY-----\n"
+          GOOGLE_SHEETS_SPREADSHEET_ID: "mock-spreadsheet-id-for-ci"
+          GOOGLE_SHEETS_SHEET_NAME: "Sheet1"
 
       - name: Upload build artifacts
         uses: actions/upload-artifact@v4

.husky/pre-commit

@@ -0,0 +1 @@
+bun run lint-staged

.prettierignore

@@ -0,0 +1,4 @@
+{
+  "recommendations": ["biomejs.biome"],
+  "unwantedRecommendations": ["dbaeumer.vscode-eslint", "esbenp.prettier-vscode"]
+}

.prettierrc

@@ -0,0 +1,27 @@
+{
+  "editor.defaultFormatter": "biomejs.biome",
+  "editor.formatOnSave": true,
+  "editor.codeActionsOnSave": {
+    "source.fixAll.biome": "explicit"
+  },
+  "[typescript]": {
+    "editor.defaultFormatter": "biomejs.biome"
+  },
+  "[typescriptreact]": {
+    "editor.defaultFormatter": "biomejs.biome"
+  },
+  "[javascript]": {
+    "editor.defaultFormatter": "biomejs.biome"
+  },
+  "[javascriptreact]": {
+    "editor.defaultFormatter": "biomejs.biome"
+  },
+  "[json]": {
+    "editor.defaultFormatter": "biomejs.biome"
+  },
+  "[jsonc]": {
+    "editor.defaultFormatter": "biomejs.biome"
+  },
+  "eslint.enable": false,
+  "prettier.enable": false
+}