fix: use macos-15-intel runner for x86_64-apple-darwin build

macos-13 has been retired by GitHub. macos-15-intel is the replacement
Intel-based macOS runner for building x86_64 binaries.

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

Author: AkiraTamai

.github/workflows/release.yml

@@ -13,7 +13,7 @@ jobs:
       matrix:
         include:
           - target: x86_64-apple-darwin
-            os: macos-13
+            os: macos-15-intel
             name: mumei-x86_64-apple-darwin
           - target: aarch64-apple-darwin
             os: macos-latest