improvement(ci): partition macOS desktop smoke coverage

Author: waleedlatif1

.github/CI.md

@@ -34,3 +34,5 @@ Every HTTP and browser group consumes the same production build in an isolated j
 The long-import and lease-expiration checks remain: they prove distinct survival/uncertain-outcome behavior across real process failure. Likewise, the two integration provision paths remain because migrations create constraints/triggers that schema push does not.
 
 Local planner validation is `bun run test:scripts scripts/ci-changes.test.ts scripts/ci-gate.test.ts`. It executes real Turbo queries in small Git fixtures; no application build or database is required. Full builds, services, browser suites, and Electron checks run on hosted CI.
+
+The separate `desktop-e2e` workflow retains its desktop-specific path filters. Its macOS shell smoke suite is partitioned by Playwright across three isolated runners; serial test-file groups stay intact. Packaging smoke and the weekly Electron canary remain separate. Each shard uploads its small JSON coverage/timing report.

.github/workflows/desktop-e2e.yml

@@ -1,6 +1,8 @@
 name: desktop-e2e
 
-# Smoke coverage of the real Electron shell on desktop changes, plus a weekly
+# Smoke coverage of the real Electron shell on desktop changes. Three isolated runners
+# partition the complete suite by Playwright test-file groups; workers remain serial per runner.
+# The weekly
 # advisory canary against electron@latest so Chromium-cadence breakage surfaces
 # before an upgrade is attempted.
 
@@ -58,10 +60,14 @@ concurrency:
 
 jobs:
   e2e:
-    name: e2e
+    name: e2e (${{ matrix.shard }}/3)
     if: github.event_name != 'schedule'
     runs-on: macos-26
     timeout-minutes: 30
+    strategy:
+      fail-fast: false
+      matrix:
+        shard: [1, 2, 3]
     steps:
       - name: Checkout code
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v6
@@ -102,19 +108,29 @@ jobs:
 
       - name: Run Playwright _electron smoke suite
         working-directory: apps/desktop
-        run: bunx playwright test
+        run: bunx playwright test --shard=${{ matrix.shard }}/3 --reporter=line,json
         env:
+          PLAYWRIGHT_JSON_OUTPUT_FILE: test-results/desktop-smoke.json
           BACKGROUND_EXECUTOR_REPORT_PATH: test-results/background-executor-report.json
           TERMINAL_CANCEL_REPORT_PATH: test-results/terminal-cancel-report.json
 
       - name: Upload test results
         if: failure()
         uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
         with:
-          name: desktop-e2e-results-pinned
+          name: desktop-e2e-results-pinned-${{ matrix.shard }}
           path: apps/desktop/test-results
           retention-days: 7
 
+      - name: Upload smoke coverage and timings
+        if: always()
+        uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
+        with:
+          name: desktop-smoke-reports-${{ matrix.shard }}
+          path: apps/desktop/test-results/desktop-smoke.json
+          if-no-files-found: ignore
+          retention-days: 7
+
   e2e-canary:
     name: e2e-canary
     if: github.event_name == 'schedule' || github.event_name == 'workflow_dispatch'