ci(release): add checks and release automation

[LMLiam]

Goal

Run Swift and native-app checks on every change and create versioned releases through release-please.

Acceptance criteria

• Pin third-party Actions to exact commit SHAs.
• Run format, SwiftPM, XcodeGen, and Xcode checks.
• Validate scoped Conventional Commit PR titles.
• Configure release-please v5 and pre-1.0 versioning.
• Keep CLI, app, manifest, and version.txt aligned.
• Use job-scoped least-privilege permissions.
• Upload the DMG only for a created release.

Owned files

CI, PR, and release workflows; release-please configuration; changelog; validation scripts and tests.

Dependencies

Local build, test, and packaging commands.

Verification

swift format lint --recursive --strict .
swift test
xcodegen generate
actionlint
bash scripts/check-version-consistency.sh
bash Tests/Scripts/run-title-tests.sh