Fix diffusion BCG lifetime and add Z-Image-Turbo CI (#30584)

.github/workflows/_pr-test-check-changes.yml

@@ -91,6 +91,7 @@ jobs:
               - ".github/workflows/pr-test-multimodal-gen.yml"
               - "python/pyproject.toml"
               - "python/sglang/multimodal_gen/**/!(*.md|*.ipynb)"
+              - "python/sglang/srt/model_executor/runner_backend_utils/breakable_cuda_graph/**"
               - "python/sglang/srt/observability/**"
               - "python/sglang/jit_kernel/**"
               - "test/registered/jit/diffusion/**"

.github/workflows/pr-test-multimodal-gen.yml

@@ -207,6 +207,61 @@ jobs:
         with:
           artifact-suffix: 1-gpu-5090
 
+  bcg-diffusion:
+    if: |
+      ((github.event_name == 'schedule' || inputs.test_parallel_dispatch == 'true') || (inputs.caller_needs_failure != 'true' && !cancelled())) &&
+      inputs.multimodal_gen == 'true'
+    runs-on: 1-gpu-h100
+    timeout-minutes: 90
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.git_ref || github.sha }}
+
+      - uses: ./.github/actions/check-pr-test-health
+
+      - uses: ./.github/actions/check-maintenance
+
+      - name: Download artifacts
+        if: inputs.sgl_kernel == 'true'
+        uses: actions/download-artifact@v4
+        with:
+          path: sgl-kernel/dist/
+          merge-multiple: true
+          pattern: wheel-python3.10-cuda*
+
+      - name: Install dependencies
+        timeout-minutes: 20
+        run: |
+          CUSTOM_BUILD_SGL_KERNEL=${{inputs.sgl_kernel}} bash scripts/ci/cuda/ci_install_dependency.sh diffusion
+
+      - name: Run BCG diffusion tests
+        timeout-minutes: 60
+        env:
+          RUNAI_STREAMER_MEMORY_LIMIT: 0
+          CONTINUE_ON_ERROR_FLAG: ${{ inputs.continue_on_error == 'true' && '--continue-on-error' || '' }}
+          SGLANG_DIFFUSION_ARTIFACT_DIR: ${{ github.workspace }}/diffusion-bcg-artifacts
+        run: |
+          cd python
+          python3 sglang/multimodal_gen/test/run_suite.py \
+            --suite bcg-diffusion \
+            $CONTINUE_ON_ERROR_FLAG
+
+      - name: Upload BCG diffusion artifacts
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: diffusion-bcg-artifacts-${{ github.run_attempt }}
+          path: diffusion-bcg-artifacts/
+          if-no-files-found: ignore
+          retention-days: 7
+
+      - uses: ./.github/actions/upload-cuda-coredumps
+        if: failure()
+        with:
+          artifact-suffix: bcg-diffusion
+
   multimodal-gen-test-2-gpu:
     needs: compute-diffusion-partitions
     if: |