refactor(ci): remove redundant build job (#180)

The test job already runs `npm run build` for all Node.js versions in
the matrix, including the latest version which matches .nvmrc. The
separate build job duplicated this work without adding value - artifact
checks are unnecessary since build failures already fail the test job.

This reduces CI time by eliminating redundant checkout, npm ci, and
build steps.

Author: groupsky

.github/workflows/ci.yml

@@ -119,36 +119,3 @@ jobs:
           fail_ci_if_error: false
         env:
           CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
-
-  build:
-    name: Build
-    runs-on: ubuntu-latest
-    needs: [setup, test]
-
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v6
-
-      - name: Setup Node.js from .nvmrc
-        uses: actions/setup-node@v6
-        with:
-          node-version-file: '.nvmrc'
-          cache: 'npm'
-
-      - name: Install dependencies
-        run: npm ci
-
-      - name: Build all packages
-        run: npm run build
-
-      - name: Check for build artifacts
-        run: |
-          if [ ! -d "packages/driver-types/dist" ]; then
-            echo "Error: driver-types build failed"
-            exit 1
-          fi
-          if [ ! -d "packages/driver-xymd1/dist" ]; then
-            echo "Error: driver-xymd1 build failed"
-            exit 1
-          fi
-          echo "All packages built successfully"