ci: 2 shards instead of 8, from measured cost

The 8-way matrix was sized against a model that over-estimated slice cost by
~10x. Run 33877144840 measured 25.8 min of sweep work in total and a 4.8 min
longest shard against a predicted 52.9, so the sweep fits the 60-minute
timeout with no sharding at all.

2 shards keeps feedback at ~12.5 min instead of ~24, for one extra repeat of
the merge and G-code stages. Eight repeats plus eight AppImage downloads bought
nothing.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TSynfTLvSnHBbVkRUm56nY

.github/workflows/cli_overrides.yml

@@ -0,0 +1,145 @@
+# CLI override sweep (orca-test-repo test_cli_overrides.py) against the
+# latest successful Linux AppImage build of this repo. Verifies every CLI
+# config option lands in the merged config and the sliced G-code's
+# CONFIG_BLOCK, then re-slices each landed option individually to classify
+# it effective/inert (--effect-full). Headless CLI only - no display stack.
+name: CLI Override Sweep
+
+on:
+  # temporary, for pre-merge branch testing: workflow_dispatch only works once
+  # the workflow exists on the default branch, but push events run the
+  # workflow from the pushed ref. Remove this trigger when merging to main.
+  push:
+    branches: ["hanif/parity-harness"]
+  workflow_dispatch:
+    inputs:
+      test_repo_ref:
+        description: "orca-test-repo ref to run"
+        required: false
+        default: "cli-test-suite"
+      build_branch:
+        description: "branch whose latest successful build_all artifact to test"
+        required: false
+        default: "main"
+
+permissions:
+  contents: read
+  actions: read
+
+jobs:
+  overrides:
+    runs-on: ubuntu-24.04
+    timeout-minutes: 60
+    strategy:
+      fail-fast: false
+      matrix:
+        # The effect stage re-slices every landed option one at a time and
+        # cannot batch, so it is the whole cost of this job.
+        # parity/effect_routing.json groups options by the cheapest fixture that
+        # can show their effect and splits them into balanced, disjoint shards
+        # covering every landed option exactly once. Measured at ~12.5 min a
+        # shard; un-sharded the sweep is ~24 min, so this is about feedback time
+        # rather than fitting the timeout.
+        shard: [0, 1]
+    steps:
+      - name: Find the latest successful Linux build
+        id: build
+        env:
+          GH_TOKEN: ${{ github.token }}
+          GH_REPO: ${{ github.repository }}
+        run: |
+          set -euo pipefail
+          gh run list --workflow build_all.yml \
+            --branch "${{ github.event.inputs.build_branch || 'main' }}" \
+            --status success --limit 1 --json databaseId,headSha \
+            --jq '"run_id=\(.[0].databaseId)\nhead_sha=\(.[0].headSha)"' \
+            >> "$GITHUB_OUTPUT"
+          cat "$GITHUB_OUTPUT"
+
+      - name: Check out the test suite
+        uses: actions/checkout@v5
+        with:
+          repository: OrcaSlicer/orca-test-repo
+          # temporary fallback for push-triggered branch testing (inputs are
+          # empty on push): restore to 'cli-test-suite' when merging to main
+          ref: ${{ github.event.inputs.test_repo_ref || 'hanif/parity-harness' }}
+          path: orca-test-repo
+
+      # the AppImage ships only packed .opc preset caches, no profile JSONs,
+      # so resources/ (and the option-surface source) must come from the
+      # source tree at the SAME sha the artifact was built from
+      - name: Check out OrcaSlicer sources at the build's sha
+        uses: actions/checkout@v5
+        with:
+          ref: ${{ steps.build.outputs.head_sha }}
+          path: slicer
+
+      - name: Download and extract the Linux AppImage
+        env:
+          GH_TOKEN: ${{ github.token }}
+          GH_REPO: ${{ github.repository }}
+        run: |
+          set -euo pipefail
+          gh run download "${{ steps.build.outputs.run_id }}" --dir appimage \
+            --pattern "OrcaSlicer_Linux_ubuntu_2404*"
+          appimage=$(find appimage -name "*.AppImage" ! -name "*aarch64*" | head -1)
+          [ -n "$appimage" ] || { echo "no AppImage found"; ls -R appimage; exit 1; }
+          chmod +x "$appimage"
+          "$appimage" --appimage-extract > /dev/null
+          [ -x squashfs-root/AppRun ] || { echo "no AppRun in AppImage"; exit 1; }
+          echo "ORCA_BIN=$PWD/squashfs-root/AppRun" >> "$GITHUB_ENV"
+          echo "ORCA_SOURCE=$PWD/slicer" >> "$GITHUB_ENV"
+
+      - name: Install the AppImage's host runtime dependencies
+        run: |
+          # orca-slicer-env's two preflight gates: OpenGL and WebKitGTK 4.1
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends \
+            libopengl0 libglu1-mesa libgl1 libegl1 libwebkit2gtk-4.1-0
+
+      - name: Install suite dependencies
+        run: pip install -r orca-test-repo/requirements.txt
+
+      - name: Run the override sweep (full effect stage)
+        id: run
+        continue-on-error: true
+        working-directory: orca-test-repo
+        run: |
+          # -rA prints the per-stage summaries: pytest captures stdout on
+          # passing tests, so without it every "grep override sweep" below
+          # finds nothing and the job summary says "no stage summaries"
+          python -m pytest test_cli_overrides.py -c pytest.ini -v -rA --effect-full \
+            --effect-shard ${{ matrix.shard }}/2 \
+            --orca-bin "$ORCA_BIN" --orca-source "$ORCA_SOURCE" \
+            2>&1 | tee ../sweep.log
+
+      - name: Publish job summary
+        if: always()
+        run: |
+          {
+            echo "## CLI override sweep - shard ${{ matrix.shard }}/2"
+            grep -E "\[override sweep" sweep.log || echo "no stage summaries (see log)"
+            echo
+            grep -E "^(=+ )?[0-9]+ (passed|failed)" sweep.log | tail -1 || true
+          } >> "$GITHUB_STEP_SUMMARY"
+
+      - name: Upload the override report
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: override-report-${{ github.run_id }}-shard${{ matrix.shard }}
+          path: |
+            orca-test-repo/.pytest_cache/override_report.json
+            sweep.log
+          if-no-files-found: warn
+          retention-days: 30
+
+      # The sweep step is continue-on-error so the summary and artifact steps
+      # above still run on a failure - without this the job would then report
+      # success, and a shard that measured nothing would look identical to a
+      # healthy one.
+      - name: Fail the job if the sweep failed
+        if: steps.run.outcome == 'failure'
+        run: |
+          echo "the override sweep failed - see the job summary and the uploaded report" >&2
+          exit 1

.github/workflows/parity.yml

@@ -0,0 +1,144 @@
+# GUI-vs-CLI parity check. Runs the parity harness from
+# OrcaSlicer/orca-test-repo (parity/) against the latest successful Linux
+# AppImage build of this repo. Metrics-only: the job never gates - its
+# product is scorecard.json / report.md, with the count of NEW divergences
+# (differences not in the harness's known-differences ledger) as the
+# headline number in the job summary.
+name: GUI-CLI Parity
+
+on:
+  # temporary, for pre-merge branch testing: workflow_dispatch only works once
+  # the workflow exists on the default branch, but push events run the
+  # workflow from the pushed ref. Remove this trigger when merging to main.
+  push:
+    branches: ["hanif/parity-harness"]
+  schedule:
+    - cron: "30 18 * * *"
+  workflow_dispatch:
+    inputs:
+      fixtures:
+        description: "space-separated fixture ids (empty = all)"
+        required: false
+        default: ""
+      test_repo_ref:
+        description: "orca-test-repo ref to run"
+        required: false
+        default: "cli-test-suite"
+      build_branch:
+        description: "branch whose latest successful build_all artifact to slice with"
+        required: false
+        default: "main"
+      cli_presets:
+        description: "lane C preset handling: flat = flatten inherits (clean parity), raw = leaf as-is (measures the CLI's unresolved-inherits behavior, expect large divergence on unfixed builds)"
+        required: false
+        default: "flat"
+
+permissions:
+  contents: read
+  actions: read
+
+jobs:
+  parity:
+    runs-on: ubuntu-24.04
+    timeout-minutes: 180
+    steps:
+      - name: Find the latest successful Linux build
+        id: build
+        env:
+          GH_TOKEN: ${{ github.token }}
+          GH_REPO: ${{ github.repository }}
+        run: |
+          set -euo pipefail
+          gh run list --workflow build_all.yml \
+            --branch "${{ github.event.inputs.build_branch || 'main' }}" \
+            --status success --limit 1 --json databaseId,headSha \
+            --jq '"run_id=\(.[0].databaseId)\nhead_sha=\(.[0].headSha)"' \
+            >> "$GITHUB_OUTPUT"
+          cat "$GITHUB_OUTPUT"
+
+      - name: Check out the parity test suite
+        uses: actions/checkout@v5
+        with:
+          repository: OrcaSlicer/orca-test-repo
+          # temporary fallback for push-triggered branch testing (inputs are
+          # empty on push): restore to 'cli-test-suite' when merging to main
+          ref: ${{ github.event.inputs.test_repo_ref || 'hanif/parity-harness' }}
+          path: orca-test-repo
+
+      # the AppImage ships only packed .opc preset caches, no profile JSONs,
+      # so resources/profiles must come from the source tree at the SAME sha
+      # the artifact was built from
+      - name: Check out OrcaSlicer sources at the build's sha
+        uses: actions/checkout@v5
+        with:
+          ref: ${{ steps.build.outputs.head_sha }}
+          path: slicer
+
+      - name: Download and extract the Linux AppImage
+        env:
+          GH_TOKEN: ${{ github.token }}
+          GH_REPO: ${{ github.repository }}
+        run: |
+          set -euo pipefail
+          gh run download "${{ steps.build.outputs.run_id }}" --dir appimage \
+            --pattern "OrcaSlicer_Linux_ubuntu_2404*"
+          # prefer the x86_64 artifact (amd64 is historically unsuffixed)
+          appimage=$(find appimage -name "*.AppImage" ! -name "*aarch64*" | head -1)
+          [ -n "$appimage" ] || { echo "no AppImage found"; ls -R appimage; exit 1; }
+          chmod +x "$appimage"
+          "$appimage" --appimage-extract > /dev/null
+          # the bare binary misses bundled libs (libavcodec etc.) - use AppRun,
+          # which sets up the AppImage's library paths and forwards arguments
+          [ -x squashfs-root/AppRun ] || { echo "no AppRun in AppImage"; exit 1; }
+          echo "ORCA_BIN=$PWD/squashfs-root/AppRun" >> "$GITHUB_ENV"
+          echo "ORCA_SLICER_ROOT=$PWD/slicer" >> "$GITHUB_ENV"
+
+      - name: Install display tooling for the GUI lanes
+        run: |
+          sudo apt-get update
+          # the AppImage's orca-slicer-env preflight requires host OpenGL and
+          # WebKitGTK 4.1 runtimes; everything else ships in the AppImage
+          sudo apt-get install -y --no-install-recommends \
+            xvfb xdotool imagemagick openbox mesa-utils \
+            libopengl0 libglu1-mesa libgl1 libegl1 libwebkit2gtk-4.1-0
+
+      - name: Run the parity harness
+        id: run
+        continue-on-error: true
+        run: |
+          set -euo pipefail
+          fixtures=""
+          for f in ${{ github.event.inputs.fixtures || '' }}; do
+            fixtures="$fixtures --fixture $f"
+          done
+          # 2 concurrent GUI displays: measured ~1.5 cores peak / ~1.9 GB on
+          # this 4-vCPU / 16 GB runner (3+ would contend); each fixture is
+          # fully isolated so this is correctness-neutral
+          python3 orca-test-repo/parity/run_parity.py \
+            --slicer-root "$ORCA_SLICER_ROOT" --bin "$ORCA_BIN" \
+            --cli-presets "${{ github.event.inputs.cli_presets || 'flat' }}" \
+            --gui-workers 2 \
+            --out "$PWD/parity-out" $fixtures
+
+      - name: Publish job summary
+        if: always()
+        run: |
+          if [ -f parity-out/report.md ]; then
+            cat parity-out/report.md >> "$GITHUB_STEP_SUMMARY"
+          else
+            echo "harness produced no report (see logs)" >> "$GITHUB_STEP_SUMMARY"
+          fi
+
+      - name: Prune bulky per-lane state before upload
+        if: always()
+        run: |
+          rm -rf parity-out/*/seed parity-out/*/datadir-* || true
+
+      - name: Upload scorecard and evidence
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: parity-scorecard-${{ github.run_id }}
+          path: parity-out/
+          if-no-files-found: warn
+          retention-days: 30