ci: introduce unified CI Quality Gate with intelligent path filtering

.github/workflows/ci.yml

@@ -17,6 +17,31 @@ on:
 permissions: read-all
 
 jobs:
+  changes:
+    name: Detect Changed Paths
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: read
+    outputs:
+      code: ${{ steps.filter.outputs.code }}
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - name: Detect Changed Paths
+        uses: dorny/paths-filter@de90cc6fb38fc0963ad72b210f1f284cd68cea36 # v3.0.2
+        id: filter
+        with:
+          filters: |
+            code:
+              - 'deploy/**'
+              - 'scripts/**'
+              - 'Makefile'
+              - 'Dockerfile*'
+              - '.github/workflows/ci.yml'
+              - '.github/workflows/release.yml'
+
   docs-match-tree:
     name: Validate Docs & Version Synchronization
     runs-on: ubuntu-latest
@@ -29,6 +54,8 @@ jobs:
 
   validate-configs:
     name: Validate Observability Manifests, Alerts & IaC
+    needs: [changes]
+    if: github.event_name == 'push' || needs.changes.outputs.code == 'true'
     runs-on: ubuntu-latest
     steps:
       - name: Checkout Code
@@ -144,6 +171,8 @@ jobs:
 
   smoke-test:
     name: Telemetry End-to-End Smoke Test
+    needs: [changes]
+    if: github.event_name == 'push' || needs.changes.outputs.code == 'true'
     runs-on: ubuntu-latest
     steps:
       - name: Checkout Code
@@ -152,3 +181,62 @@ jobs:
       - name: Run End-to-End Telemetry Smoke Test
         run: bash ./scripts/smoke_test.sh
 
+  ci-gate:
+    name: CI Quality Gate
+    runs-on: ubuntu-latest
+    if: always()
+    needs:
+      - changes
+      - docs-match-tree
+      - validate-configs
+      - smoke-test
+    steps:
+      - name: Evaluate CI Quality Gate
+        run: |
+          echo "========================================================"
+          echo "🏁 Evaluating CI Quality Gate"
+          echo "   Event: ${{ github.event_name }}"
+          echo "   Code changes detected: ${{ needs.changes.outputs.code }}"
+          echo "========================================================"
+
+          if [ "${{ needs.changes.result }}" != "success" ]; then
+            echo "❌ Path detection failed with: ${{ needs.changes.result }}" >&2
+            exit 1
+          fi
+
+          if [ "${{ needs.docs-match-tree.result }}" != "success" ]; then
+            echo "❌ Documentation & Version Gate failed with: ${{ needs.docs-match-tree.result }}" >&2
+            exit 1
+          fi
+
+          SHOULD_VERIFY_CODE="${{ github.event_name == 'push' || needs.changes.outputs.code == 'true' }}"
+          if [ "$SHOULD_VERIFY_CODE" = "true" ]; then
+            echo "🔍 Verifying code & infrastructure test suites..."
+            FAILED=0
+
+            if [ "${{ needs.validate-configs.result }}" != "success" ]; then
+              echo "❌ Validate Observability Manifests, Alerts & IaC: ${{ needs.validate-configs.result }}" >&2
+              FAILED=1
+            else
+              echo "✅ Validate Observability Manifests, Alerts & IaC: success"
+            fi
+
+            if [ "${{ needs.smoke-test.result }}" != "success" ]; then
+              echo "❌ Telemetry End-to-End Smoke Test: ${{ needs.smoke-test.result }}" >&2
+              FAILED=1
+            else
+              echo "✅ Telemetry End-to-End Smoke Test: success"
+            fi
+
+            if [ "$FAILED" -ne 0 ]; then
+              echo "❌ CI Quality Gate failed." >&2
+              exit 1
+            fi
+          else
+            echo "📄 Docs-only change detected. Heavy infrastructure validation and smoke tests safely skipped."
+          fi
+
+          echo "========================================================"
+          echo "✅ All CI Quality Gates successfully satisfied!"
+          echo "========================================================"
+