refactor: update CI workflows for Biome, remove duplicate workflows

- Replace ESLint job with Biome check in lint.yml
- Remove duplicate build.yml and CI.yml (covered by deploy.yml + lint.yml)

Author: matsuzaka-yuki

.github/workflows/CI.yml

@@ -15,8 +15,8 @@ permissions:
   contents: read
 
 jobs:
-  eslint:
-    name: ESLint
+  biome:
+    name: Biome Check
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
@@ -33,20 +33,8 @@ jobs:
       - name: Install dependencies
         run: pnpm install --frozen-lockfile
 
-      - name: Create ESLint output directory
-        run: mkdir -p eslint-results
-
-      - name: Run ESLint
-        run: pnpm lint --format=json --output-file=eslint-results/eslint-results.json
-        continue-on-error: true
-
-      - name: Upload ESLint results
-        if: always()
-        uses: actions/upload-artifact@v4
-        with:
-          name: eslint-results-${{ github.run_id }}
-          path: eslint-results/
-          retention-days: 7
+      - name: Run Biome Check
+        run: pnpm lint
 
   typecheck:
     name: Type Check
@@ -70,3 +58,26 @@ jobs:
         run: pnpm astro check
         env:
           ENABLE_CONTENT_SYNC: false
+
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v6
+        with:
+          node-version: lts/*
+
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile
+
+      - name: Build
+        run: pnpm build
+        env:
+          ENABLE_CONTENT_SYNC: false