Build native Launchd TOC app

[thierryc]

Summary

• build an original Swift 6 and SwiftUI macOS 26 utility for launchd inventory and safe user-agent management
• add structured format-preserving plist editing, launchctl lifecycle actions, schedule previews, bounded logs, and explicit stable update checks
• add the original app icon, clean-room provenance, architecture and release documentation, tests, CI, and a Developer ID notarized DMG workflow

Safety

• only direct non-symlink plist files under the current user LaunchAgents directory can be changed
• global and Apple services are read-only; Apple services are hidden by default
• process execution is restricted to fixed Apple executable URLs and argument arrays
• no administrator access, analytics, accounts, helper, automatic network requests, or sandbox entitlement

Verification

• Swift 6 strict-concurrency builds with warnings treated as errors
• arm64 and x86_64 unit suites pass
• macOS UI test suite passes locally with development signing
• static analysis passes
• universal Developer ID archive passes codesign, hardened-runtime, team, bundle ID, architecture, and entitlement checks
• beta DMG passes Developer ID signature and hdiutil checksum validation

Release note

No tag is created by this PR. The first notarized download remains v0.1.0-beta.1 after the documented GitHub Actions secrets are configured.