go back to macOS 13 for Intel

there are no other free macOS Intel gh
action runners for opensource projects. :-(

the macOS 13 runner is deprecated, so guess
it will be game-over for macOS Intel 2025-12.

.github/workflows/ci.yml

@@ -62,7 +62,7 @@ jobs:
               {"os": "ubuntu-24.04", "python-version": "3.12", "toxenv": "py312-fuse3"},
               {"os": "ubuntu-24.04", "python-version": "3.13", "toxenv": "py313-fuse3"},
               {"os": "ubuntu-24.04", "python-version": "3.14", "toxenv": "py314-fuse3"},
-              {"os": "macos-14-large", "python-version": "3.11", "toxenv": "py311-none", "binary": "borg-macos-14-x86_64-gh"},
+              {"os": "macos-13", "python-version": "3.11", "toxenv": "py311-none", "binary": "borg-macos-13-x86_64-gh"},
               {"os": "macos-14", "python-version": "3.11", "toxenv": "py311-none", "binary": "borg-macos-14-arm64-gh"}
             ]
           }'

docs/binaries/00_README.txt

@@ -35,7 +35,7 @@ borg-linux-glibc235-x86_64-gh Linux AMD/Intel (built on Ubuntu 22.04 LTS with gl
 borg-linux-glibc235-arm64-gh  Linux ARM (built on Ubuntu 22.04 LTS with glibc 2.35)
 
 borg-macos-14-arm64-gh        macOS Apple Silicon (built on macOS 14 w/o FUSE support)
-borg-macos-14-x86_64-gh       macOS Intel (built on macOS 14 w/o FUSE support)
+borg-macos-13-x86_64-gh       macOS Intel (built on macOS 13 w/o FUSE support)
 
 
 Binaries built locally