fix(ci): add contents:write permission to build-engine workflow

The GITHUB_TOKEN needs contents:write to create GitHub releases.
Without it, the `gh release create` step fails with HTTP 403.

Author: Broccolito

.github/workflows/build-engine.yml

@@ -11,6 +11,8 @@ jobs:
   build:
     name: Build all platform bundles
     runs-on: ubuntu-latest
+    permissions:
+      contents: write
     steps:
       - uses: actions/checkout@v4
       - name: Set up Node