Crash reporting integration

[ryanabooth]

Get crash data flowing so post-launch issues are visible without waiting for App Store reviews.

Options

1. TestFlight + Xcode Organizer (built-in) — free, requires user opt-in, surfaces in Organizer. Zero new dependencies. Good enough for v1.0.
2. Sentry (or Bugsnag, Embrace, etc.) — paid, richer breadcrumbs and session replay. Worth it once user count justifies the spend.

Recommended path: ship with the built-in flow for v1.0, document the wrapper interface so we can swap in Sentry later without touching call sites.

Scope (built-in flow)

• Verify TestFlight feedback is enabled in App Store Connect
• Document the "View crash logs" workflow in CLAUDE.md so future agents know where to look
• Add a small CrashReporter no-op wrapper at the boundary, ready for Sentry-or-similar to drop in later

Scope (Sentry, if we go that route)

• Sentry account + DSN
• Sentry SPM dependency added to the LifePlanner target
• SentrySDK.start in AppDelegate.application(_:didFinishLaunchingWithOptions:)
• User-opt-in toggle in Settings (privacy-respectful)

Acceptance criteria

• At least one crash report observed end-to-end (Settings → cause a deliberate crash → confirm it appears)
• Documented in CLAUDE.md