Full-feature v3 showcase example app + library fixes

[MoElnaggar14]

Summary

Rewrites ExampleApp/SwiftMoLoggerExample from a 3-tab minimal demo into an end-to-end showcase that links and exercises every product in the package — so the app can be handed to a teammate (or to other apps' maintainers) and demonstrate the full v3 surface in one binary.

Also fixes a handful of library bugs surfaced while wiring the showcase.

Library fixes (commit 1)

• FlightRecorder.defaultFileURL — was internal but used as the default arg of the public recoverLastSession(from:); promoted to public so adopters can actually call the API without a URL.
• FlightRecorder.start() — always registers this recorder's private MemoryLogEngine. The previous check skipped registration whenever any MemoryLogEngine existed in the registry, silently breaking recording for adopters who wire their own first.
• MetricKitCrashReporter — MXHangDiagnostic.hangDuration is a Measurement<UnitDuration> on iOS 17+ SDK, not NSNumber-coercible. Converted via .converted(to: .milliseconds).value.
• LogConsoleViewModel.entries — relaxed to internal(set) so @testable tests can seed entries directly (matched the existing tests).
• FlightRecorderTests — added a setUp that resets the global registry + minimum level so previous-suite leftovers don't mask captured entries.
• Package.swift platforms — bumped to iOS 16 / macOS 13 / tvOS 16 / watchOS 9. The UI module already uses NavigationStack + LabeledContent unguarded, so the iOS 15 declaration was incorrect.

All 70 tests pass after the changes.

Showcase app (commit 2)

• xcodeproj: links SwiftMoLoggerUI / Network / Diagnostics / Remote / Sugar (previously only SwiftMoLogger was wired even though ContentView already imported UI). Deployment target → iOS 17.
• SwiftMoLoggerExampleApp.configureLogging() boots the full stack in one function: Memory + System engines, ErrorGroupingEngine, RedactingLogEngine, a file engine wrapped in SamplingLogEngine + RateLimitingLogEngine, NetworkLogger.installOnSharedSession(), AppVitalsMonitor, and a FlightRecorder.
• Six tabs:
  • Demo — every log level, error(Error), breadcrumbs, LogSignpost.measure + nested spans, the #log / #measure / @AutoLog macros, withContext, withTrace (W3C traceparent), regex redaction, and error grouping.
  • Console — bundled LogConsoleView.
  • Hub — bundled DiagnosticsHubView (timeline, network waterfall, flame graph, vitals charts, breadcrumb trail).
  • Network — real httpbin.org requests (200 / 404 / 500 / inside withTrace) flowing through NetworkLoggingProtocol, populating the Hub's waterfall and breadcrumbs live.
  • Diagnostics — live AppVitalsMonitor sample, FlightRecorder status, one-tap BugReporter bundle with ShareLink, Bonjour LiveSink toggle, and snippets for Sentry / Datadog / Loki / MetricKit.
  • About — full feature matrix for talking-points.

Test plan

• swift test — 70/70 pass
• xcodebuild -scheme SwiftMoLoggerExample -destination 'generic/platform=iOS Simulator' build succeeds
• ⌘R on a simulator, click through each tab — verify Hub populates after a few minutes of activity
• Verify the redaction tab actually shows [REDACTED] in the Console
• Toggle LiveSink and confirm swiftmologger-inspector on macOS sees the Bonjour service