Migrate away from the macos-13 runner

Author: mtkennerly

.github/workflows/main.yaml

@@ -24,7 +24,7 @@ jobs:
             artifact-name: linux
             artifact-file: madamiru
             tar: true
-          - os: macos-13
+          - os: macos-14
             rust-target: x86_64-apple-darwin
             artifact-name: mac
             artifact-file: madamiru
@@ -80,7 +80,7 @@ jobs:
         os:
           - windows-latest
           - ubuntu-22.04
-          - macos-13
+          - macos-14
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4

CHANGELOG.md

@@ -1,3 +1,9 @@
+## Unreleased
+
+* Changed:
+  * The standalone Mac release is now compiled on Mac OS 14 instead of Mac OS 13
+    because of [a change by GitHub](https://github.com/actions/runner-images/issues/13046).
+
 ## v0.3.0 (2025-08-06)
 
 * Added: