[ci]: Add workflow to guard against growing bundle size

.github/workflows/check_bundle.yml

@@ -0,0 +1,76 @@
+name: Bundle Size Check
+on:
+  pull_request:
+    branches: [main]
+
+  push:
+    branches: [main]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ (github.event.pull_request && github.event.pull_request.number) || github.ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  build-and-check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4.2.1
+
+      - name: Read .npmrc
+        id: npmrc
+        run: |
+          NODE_VERSION=$(grep 'node=' .npmrc | cut -d'=' -f2)
+          echo "node_version=$NODE_VERSION" >> $GITHUB_OUTPUT
+
+      - name: Setup Node.js
+        uses: actions/setup-node@39370e3970a6d050c480ffad4ff0ed4d3fdee5af # v4.1.0
+        with:
+          node-version: ${{ steps.npmrc.outputs.node_version }}
+          cache: 'npm'
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Build
+        run: npm run build
+
+      - name: Calculate bundle size
+        run: |
+          TOTAL_SIZE=$(du -sb packages/jaeger-ui/build | cut -f1)
+          echo "$TOTAL_SIZE" > new_bundle_size.txt
+          echo "Total bundle size: $TOTAL_SIZE bytes"
+
+      - name: Restore previous bundle size
+        id: cache-bundle-size
+        uses: actions/cache@v4
+        with:
+          path: bundle_size.txt
+          key: bundle-size-jaeger-ui
+
+      - name: Compare bundle sizes
+        if: steps.cache-bundle-size.outputs.cache-hit == 'true'
+        run: |
+          OLD_BUNDLE_SIZE=$(cat bundle_size.txt)
+          NEW_BUNDLE_SIZE=$(cat new_bundle_size.txt)
+          echo "Previous bundle size: $OLD_BUNDLE_SIZE bytes"
+          echo "New bundle size: $NEW_BUNDLE_SIZE bytes"
+
+          SIZE_CHANGE=$(( $NEW_BUNDLE_SIZE - $OLD_BUNDLE_SIZE ))
+          PERCENTAGE_CHANGE=$(( SIZE_CHANGE * 100 / $OLD_BUNDLE_SIZE ))
+          echo "Size change: $PERCENTAGE_CHANGE%"
+          if [ $PERCENTAGE_CHANGE -gt 2 ]; then
+            echo "❌ Bundle size increased by more than 2% ($PERCENTAGE_CHANGE%)"
+            exit 1
+          else
+            echo "✅ Bundle size change is within acceptable range ($PERCENTAGE_CHANGE%)"
+          fi
+
+      - name: Update bundle size file
+        run: mv new_bundle_size.txt bundle_size.txt
+
+      - name: Save new bundle size
+        if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+        uses: actions/cache/save@v4
+        with:
+          path: bundle_size.txt
+          key: bundle-size-jaeger-ui