ci: handle Electron app artifact shape

Wraps downloaded Contents folder back into OpenChamber.app
Unblocks Tauri-to-Electron migration repackage job
Documents GitHub artifact behavior

.github/workflows/release.yml

@@ -305,9 +305,14 @@ jobs:
           set -euo pipefail
 
           if [ ! -d staged/OpenChamber.app ]; then
-            echo "Error: staged/OpenChamber.app not found"
+            if [ -d staged/Contents ]; then
-            ls -la staged
+              mkdir -p staged/OpenChamber.app
-            exit 1
+              mv staged/Contents staged/OpenChamber.app/Contents
+            else
+              echo "Error: staged/OpenChamber.app not found"
+              ls -la staged
+              exit 1
+            fi
           fi
 
           cd staged

docs/TAURI_TO_ELECTRON_CUTOVER.md

@@ -114,6 +114,11 @@ only verifies the signature and extracts the bundle over the existing
 `/Applications/OpenChamber.app`. After restart, the app is Electron and future
 updates use `latest-mac.yml` through `electron-updater`.
 
+Note: `actions/upload-artifact` can download a `.app` directory artifact as its
+inner `Contents/` folder instead of `OpenChamber.app/Contents`. The repackage
+job handles both shapes and wraps `Contents/` back into `OpenChamber.app` before
+creating the tarball.
+
 ## Historical release workflow changes
 
 The file edited for the cutover was `.github/workflows/release.yml`.