build: remove sourcemaps for deterministic dist

Sourcemaps embed absolute paths which differ between build
environments, causing CI to fail. GitHub Actions don't need
sourcemaps anyway.

Author: SamMorrowDrums

.github/workflows/ci.yml

@@ -44,5 +44,5 @@ jobs:
       - name: Verify dist is up to date
         if: matrix.node-version == 20
         run: |
-          # Check if main dist file is up to date (ignore sourcemaps which can differ between environments)
-          git diff --exit-code dist/index.js || (echo "::error::dist/index.js is out of date. Run 'npm run build' and commit the changes." && exit 1)
+          # Check if dist files are up to date
+          git diff --exit-code dist/ || (echo "::error::dist/ is out of date. Run 'npm run build' and commit the changes." && exit 1)