ci: support prerelease macOS builds

[vuon9]

Summary

• opt CI into Node 24 JavaScript actions to clear the cache restore deprecation warning
• mark GitHub Releases as prereleases when the tag contains a prerelease suffix
• accept prerelease SemVer tags like v0.10.0-rc.1 while embedding the stable base version in the macOS app bundle

Verification

• ruby -e 'require "yaml"; %w[.github/workflows/ci.yml .github/workflows/release.yml].each { |path| YAML.load_file(path); puts "yaml ok #{path}" }'\n- bash -n scripts/package-macos-universal.sh\n- prerelease tag derivation smoke test: v0.10.0-rc.1 -> 0.10.0\n\n## Known Existing Failure\n- go test ./... still fails in cmd/testserver: undefined: service.NewConversionService. The GitHub CI backend job only tests ./internal/... and passed on main before this branch.

[github-actions]

Package	Line Rate	Health
devtoolbox/internal/barcode	93%	✔
devtoolbox/internal/codeformatter	80%	➖
devtoolbox/internal/converter	65%	➖
devtoolbox/internal/datagenerator	81%	✔
devtoolbox/internal/datetimeconverter	75%	➖
devtoolbox/internal/jwt	47%	❌
devtoolbox/internal/numberconverter	98%	✔
devtoolbox/internal/settings	0%	❌
devtoolbox/internal/themes	0%	❌
Summary	70% (3726 / 5294)	➖

Minimum allowed line rate is 60%