ci(ux): add independent Linux and Windows UX platform contract

.github/workflows/ux-platform-contract.yml

@@ -0,0 +1,51 @@
+name: Vendoo UX Platform Contract
+
+on:
+  push:
+    branches: [main, develop, 'feature/**', 'release/**', 'hotfix/**']
+  pull_request:
+    branches: [main, develop]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: vendoo-ux-platform-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  ux-platform-contract:
+    name: UX Platform (${{ matrix.os }})
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 10
+    steps:
+      - name: Repository auschecken
+        uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+
+      - name: Node.js 22 aktivieren
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22.x'
+          cache: npm
+
+      - name: Abhängigkeiten reproduzierbar installieren
+        run: npm ci
+
+      - name: Navigation API und Safe Actions prüfen
+        run: node tools/run-ux-platform-gates.mjs
+
+      - name: UX-Plattformdiagnose sichern
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: ux-platform-${{ matrix.os }}-${{ github.event.pull_request.head.sha || github.sha }}
+          path: artifacts/ux-platform-gates.log
+          if-no-files-found: error
+          retention-days: 14