Test librarian with new wrkflw

.github/workflows/experiment.yaml

@@ -0,0 +1,169 @@
+name: Next-Gen CI Pipeline
+
+on:
+  pull_request:
+    branches: [ main, preview ]
+  # Native Merge Queue support for exhaustive batching
+  merge_group:
+    types: [checks_requested]
+
+# Stop burning money on abandoned iterative commits
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  # ==========================================
+  # 1. DISCOVERY ENGINE (The Router)
+  # ==========================================
+  discover:
+    runs-on: ubuntu-latest
+    outputs:
+      packages: ${{ steps.changes.outputs.all_changed_files }}
+      # Expose the dynamic Python matrix to downstream jobs
+      python_versions: ${{ steps.set-python.outputs.matrix }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Detect Changed Packages
+        id: changes
+        uses: tj-actions/changed-files@v44
+        with:
+          files: packages/**
+          dir_names: true               
+          dir_names_max_depth: 2        
+          json: true                    
+          escape_json: false
+
+      - name: Determine Python Matrix (Risk-Tiering)
+        id: set-python
+        run: |
+          if [[ "${{ github.event_name }}" == "merge_group" ]]; then
+            echo "Merge Queue detected. Deploying exhaustive matrix."
+            echo 'matrix=["3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]' >> $GITHUB_OUTPUT
+          else
+            echo "Pull Request detected. Deploying Min/Max Boundary matrix."
+            echo 'matrix=["3.9", "3.14"]' >> $GITHUB_OUTPUT
+          fi
+
+  # ==========================================
+  # 2. STATIC ANALYSIS (Grouped for Speed)
+  # ==========================================
+  static-checks:
+    needs: discover
+    if: ${{ needs.discover.outputs.packages != '[]' }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false 
+      matrix:
+        package: ${{ fromJSON(needs.discover.outputs.packages) }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: astral-sh/setup-uv@v5
+        with:
+          python-version: "3.14" 
+          enable-cache: true
+          cache-dependency-glob: "${{ matrix.package }}/setup.py"
+
+      - name: Run Lint and MyPy
+        run: |
+          cd ${{ matrix.package }}
+          export NOX_DEFAULT_VENV_BACKEND=uv
+          export UV_VENV_SEED=1
+          uvx --with 'nox[uv]' nox -s lint mypy lint_setup_py
+
+  # ==========================================
+  # 3. DOCUMENTATION BUILD
+  # ==========================================
+  docs-build:
+    needs: discover
+    if: ${{ needs.discover.outputs.packages != '[]' }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        package: ${{ fromJSON(needs.discover.outputs.packages) }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: astral-sh/setup-uv@v5
+        with:
+          python-version: "3.10"
+          enable-cache: true
+          cache-dependency-glob: "${{ matrix.package }}/setup.py"
+
+      - name: Build Docs and DocFX
+        run: |
+          cd ${{ matrix.package }}
+          export NOX_DEFAULT_VENV_BACKEND=uv
+          export UV_VENV_SEED=1
+          uvx --with 'nox[uv]' nox -s docs docfx
+
+  # ==========================================
+  # 4. UNIT TESTS (Dynamic 2D Matrix + Retries)
+  # ==========================================
+  unit-tests:
+    needs: discover
+    if: ${{ needs.discover.outputs.packages != '[]' }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        package: ${{ fromJSON(needs.discover.outputs.packages) }}
+        # Reads the array generated by the Discovery job
+        python: ${{ fromJSON(needs.discover.outputs.python_versions) }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: astral-sh/setup-uv@v5
+        with:
+          python-version: ${{ matrix.python }}
+          enable-cache: true
+          cache-dependency-glob: "${{ matrix.package }}/setup.py"
+
+      - name: Execute Unit Tests (With Shock Absorbers)
+        run: |
+          cd ${{ matrix.package }}
+          export NOX_DEFAULT_VENV_BACKEND=uv
+          export UV_VENV_SEED=1
+          export UV_COMPILE_BYTECODE=1
+
+          # 3-Attempt retry loop to mask legacy flaky tests
+          for i in 1 2 3; do
+            echo "Attempt $i of 3 for Python ${{ matrix.python }}..."
+            if uvx --with 'nox[uv]' nox -s unit-${{ matrix.python }}; then
+              echo "Tests passed successfully!"
+              exit 0
+            fi
+            echo "Tests failed. Waiting 5 seconds before retrying..."
+            sleep 5
+          done
+
+          echo "::error::Tests failed after 3 attempts. This is a hard failure."
+          exit 1
+
+  # ==========================================
+  # 6. THE GATEKEEPER (Status Check Rollup)
+  # ==========================================
+  presubmit-passed:
+    if: always() 
+    needs: 
+      - discover
+      - static-checks
+      - docs-build
+      - unit-tests
+    runs-on: ubuntu-latest
+    steps:
+      - name: Evaluate Pipeline Status
+        run: |
+          if [[ "${{ contains(needs.*.result, 'failure') }}" == "true" || "${{ contains(needs.*.result, 'cancelled') }}" == "true" ]]; then
+            echo "::error::One or more required CI jobs failed or were cancelled."
+            exit 1
+          fi
+
+          if [[ "${{ needs.discover.outputs.packages }}" == "[]" ]]; then
+            echo "No Python packages changed. Safely bypassing execution."
+            exit 0
+          fi
+
+          echo "All dynamically generated CI jobs completed successfully."