perf(test): speed up local and CI validation

.github/workflows/ci.yml

@@ -82,7 +82,7 @@ jobs:
 
   test-shard:
     name: Test shard (${{ matrix.shard }})
-    needs: changes
+    needs: [changes, build]
     if: github.event_name == 'push' || needs.changes.outputs.code == 'true'
     runs-on: ubuntu-latest
     strategy:
@@ -96,7 +96,11 @@ jobs:
           node-version-file: .nvmrc
           cache: npm
       - run: npm ci
-      - run: npm run test:ci:shard -- --shard=${{ matrix.shard }}
+      - uses: actions/download-artifact@v4
+        with:
+          name: rea-dist
+          path: dist
+      - run: npm run test:ci:shard:run -- --shard=${{ matrix.shard }}
       - uses: actions/upload-artifact@v4
         if: ${{ !cancelled() }}
         with:
@@ -107,6 +111,26 @@ jobs:
           overwrite: true
           retention-days: 1
 
+  build:
+    name: Build package
+    needs: changes
+    if: github.event_name == 'push' || needs.changes.outputs.code == 'true'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version-file: .nvmrc
+          cache: npm
+      - run: npm ci
+      - run: npm run build:cached
+      - uses: actions/upload-artifact@v4
+        with:
+          name: rea-dist
+          path: dist
+          if-no-files-found: error
+          retention-days: 1
+
   test:
     name: Test (coverage + timing)
     needs: [changes, test-shard]