switch to macos-15 to get xcode 16.4

Author: CISC

.github/workflows/release.yml

@@ -600,7 +600,7 @@ jobs:
           name: llama-bin-win-hip-${{ matrix.name }}-x64.zip
 
   ios-xcode-build:
-    runs-on: macos-latest
+    runs-on: macos-15
 
     steps:
       - name: Checkout code
@@ -610,7 +610,7 @@ jobs:
 
       - name: Setup Xcode
         run: |
-          sudo xcode-select -s /Applications/Xcode_16.4.app/Contents/Developer
+          sudo xcode-select -s /Applications/Xcode_16.4.app
 
       - name: Build
         id: cmake_build