ci: upgrade macos-14 runners to macos-15

[joshuarli]

Summary

• Upgrade macos-14 GitHub Actions runners (and macos-14-large / macos-14-xlarge) to macos-15 in .github/
• Where a matrix already lists macos-15, drop the macos-14 entry instead of duplicating it

Why

GitHub is retiring the macOS 14 runner images. Deprecation began July 6, 2026 and the
images are fully unsupported on November 2, 2026, after which jobs using these labels
are terminated with an error.

Before that, GitHub runs brownouts that deliberately fail macos-14 jobs, the first
on October 5 (14:00-00:00 UTC), with more through October 30. See
actions/runner-images#13518.

Review notes

macos-15 ships different Xcode and simulator versions than macos-14. If a job pins an
Xcode or iOS simulator version, or pinned macos-14 on purpose to get an older one, check
that it still works on macos-15.

Generated by macos-15.

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Pinned Xcode missing on macos-15

High Severity

Jobs now run on macos-15 but still select /Applications/Xcode_15.4.app, which is not installed on that image. The xcode-select step fails immediately, so pull request builds, XCFramework builds, and the release workflow cannot complete.

Additional Locations (2)

• .github/workflows/build-xcframework.yml#L15-L16
• .github/workflows/release.yaml#L15-L16

 

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[sentry]

Bug: The workflows specify using Xcode_15.4.app on macos-15 runners, but this version of Xcode is likely unavailable, which will cause the jobs to fail.
_{Severity: CRITICAL}

Suggested Fix

Verify the available Xcode versions on the macos-15 runner image. Update the xcode-version input in the affected workflow jobs to a version confirmed to be installed on macos-15, which is likely a version of Xcode 16.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location: .github/workflows/build.yml#L8-L13

Potential issue: The GitHub Actions workflows specify using `Xcode_15.4.app` on
`macos-15` runners. However, it is likely that the `macos-15` runner images provided by
GitHub do not include this version of Xcode, and may only contain Xcode 16.x versions.
If `Xcode_15.4.app` is not installed on the runner, the `xcode-select` command will
fail, causing the build and release jobs to fail. The pull request description's note to
check compatibility suggests this is a known risk. This issue affects multiple build
jobs across different workflows, including the critical release pipeline.

Also affects:

• .github/workflows/build.yml:22~27
• .github/workflows/build.yml:50~55
• .github/workflows/build.yml:64~69
• .github/workflows/build.yml:78~83
• .github/workflows/build-xcframework.yml:8~13
• .github/workflows/release.yaml:8~13

_{Did we get this right? 👍 / 👎 to inform future reviews.}