feat(release): build native macOS installers

[nkavian]

Summary

• build macOS release artifacts on native arm64 and x64 runners
• render a multi-architecture Homebrew Cask from separate checksums
• point install and update messaging at https://inflowcli.ai/ instead of npm-specific commands

Verification

• pnpm typecheck
• pnpm lint
• pnpm test
• pnpm typedoc
• pnpm build
• pnpm format:check
• workflow YAML parse check
• local arm64 macOS app package build with ad hoc signing
• multi-architecture Homebrew Cask render with dummy artifacts and ruby -c

Notes

• Hosted install.sh/install.ps1 live in inflow-server and need a separate repo change.
• Real notarized release remains parked until Apple notarization is behaving normally.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!