ci(desktop): add GitHub Actions workflow for Swift tests

Use reusable swift-ci workflow from plexusone/.github for build and test.

Triggers on push/PR to main when apps/desktop/** changes.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: grokify

.github/workflows/desktop.yml

@@ -0,0 +1,20 @@
+name: Desktop CI
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - 'apps/desktop/**'
+      - '.github/workflows/desktop.yml'
+  pull_request:
+    branches: [main]
+    paths:
+      - 'apps/desktop/**'
+      - '.github/workflows/desktop.yml'
+
+jobs:
+  swift-ci:
+    name: Swift CI
+    uses: plexusone/.github/.github/workflows/swift-ci.yaml@main
+    with:
+      working-directory: apps/desktop