feat(mobile): in-app debug logging with file export

[JordiMa]

Why

User-reported issues (like the recent Android push-activation reports) are hard to diagnose without visibility into what happened on the device. This adds an in-app debug log that users can export and attach to a bug report.

What

Logger (core/logging/)

• appLogger singleton with info/warn/error(tag, message, data?).
• Ring buffer of 5000 entries; consecutive duplicates are collapsed into one entry with a repeat counter (GET /alerts → 200 | 91ms (×3)), so the 30s alerts poll no longer eats the buffer. Attached data is truncated at 300 chars.
• Persistent across sessions: debounced (1s) writes to a JSON file via expo-file-system on native, localStorage on web. Error-level entries are flushed immediately so they survive a crash.
• Logging is fail-safe end to end (storage errors are swallowed).

What gets captured (central choke points, no per-screen wiring)

• Every API request: method, path (query strings stripped), status, duration; network failures; session-refresh failures.
• Every user interaction: taps, toggles, list rows and segment selections — logged inside the four core UI components (GlassButton, AppSwitch, ListRow, SegmentedControl).
• Navigation: active screen on every navigation state change (nested navigators resolved) + shell gate transitions (Auth/Consent/Onboarding/Main).
• Global JS errors: a wrapper around ErrorUtils logs fatal/non-fatal errors (name, message, stack head) before delegating to the previous handler.
• Lifecycle & auth: session start (app version, platform), app foregrounding, token stored/cleared, login-callback outcomes (token received / missing scopes), Tesla-login open failures.
• Push flow: token sync, permission missing → auto-disable, device registration, notification-preference updates (payload is boolean-only), logout cleanup failures.
• Never logged: JWT/Tesla tokens (only their presence), push token (last 8 chars only), request bodies, text-input values, URLs with parameters.

Export UI (Settings → Support)

• Export debug logs: writes sentryguard-logs-<date>.txt and opens the native share sheet via expo-sharing (falls back to a plain-text share if unavailable; downloads the file on web).
• Clear debug logs.
• en/fr localization.

Dependencies

• expo-file-system ~19.0.23 — already shipped in every build (dependency of the expo package), now declared directly. No native rebuild needed for it.
• expo-sharing ~14.0.8 — new native module: works in Expo Go now, standalone builds need the next native build (until then the text-share fallback applies).
• yarn install --immutable verified.

Tests

• 16 new logger tests (formatting, truncation, ring-buffer limit, duplicate collapsing, persistence across sessions, immediate error flush, debounced flush) + coverage for the global error handler and nested-route resolution.
• Full suite: 148/148, nx typecheck mobile, lint and nx export mobile all pass.

Notes

• Small, expected merge overlaps with fix(mobile): recover push activation when the notification permission is blocked #181 (settings.helpers.ts, locales) — trivial to resolve whichever lands first.
• Sample export:

SentryGuard debug logs
Exported at: 2026-07-03T21:26:36.953Z
App version: 1.0.0
Platform: android 36
Entries: 41
---
2026-07-03T21:26:10.338Z [INFO] app: Session started (v1.0.0, android 36)
2026-07-03T21:26:10.556Z [INFO] nav: Shell gate → Main
2026-07-03T21:26:12.095Z [INFO] api: GET /notifications/preferences → 200 | 54ms
2026-07-03T21:26:26.224Z [INFO] ui: Toggle "Notifications push" → false
2026-07-03T21:26:26.316Z [INFO] settings: Notification preference update | {"push_enabled":false,"critical_alerts_enabled":false}