Revert "Update to Xcode 26.1"

This reverts commit 39d55b7e39.

.github/workflows/main.yml

@@ -18,7 +18,7 @@ concurrency:
 
 env:
   # Path format pulled from https://github.com/actions/runner-images/blob/main/images/macos/macos-15-Readme.md#xcode
-  DEVELOPER_DIR: /Applications/Xcode_26.1.app
+  DEVELOPER_DIR: /Applications/Xcode_26.0.app
 
 jobs:
   build_and_test:
@@ -31,7 +31,7 @@ jobs:
     strategy:
       matrix:
         # Add additional Xcode versions here if necessary.
-        xcode: ["Xcode_26.1", "Xcode_16.4"]
+        xcode: ["Xcode_26.0", "Xcode_16.4"]
 
     steps:
       - name: Set Xcode version
@@ -46,7 +46,7 @@ jobs:
           Scripts/check_xcode_version.py --relaxed
 
       - name: Download Metal toolchain
-        if: ${{ matrix.xcode == 'Xcode_26.1' }}
+        if: ${{ matrix.xcode == 'Xcode_26.0' }}
         run: |
           xcodebuild -downloadComponent MetalToolchain
 

.xcode-version

@@ -1 +1 @@
-Xcode 26.1
+Xcode 26.0.1