ENG-219: Add build step before running tests in CI

Tests spawn node dist/cli.js, so the project must be built first.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: d4mation

.github/workflows/tests.yml

@@ -12,6 +12,7 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
       - run: npm ci
+      - run: npm run build
       - name: Setup git
         run: |
           git config --global user.name "GitHub Actions"