Add getLeaveStatus utility and update project status

- Introduce `getLeaveStatus` function in `packages/core/src/status-utils.ts` to determine leave-by status based on
  journey data
- Mark Phase 1 mobile app tasks as complete in `CHECKLIST.md`
- Add mobile workspace configurations and npm scripts

apps/mobile/src/store/eventStore.ts

@@ -0,0 +1,77 @@
+import AsyncStorage from '@react-native-async-storage/async-storage';
+import type { Event, Station, ReminderSettings } from '@timetoleave/core';
+
+// ── Keys ────────────────────────────────────────────
+
+const EVENTS_KEY = '@timetoleave_events';
+const ORIGIN_KEY = '@timetoleave_origin';
+const NOTIFICATIONS_KEY = '@timetoleave_notifications';
+
+// ── Default notification settings ─────────────────────
+
+const DEFAULT_NOTIFICATION_SETTINGS: ReminderSettings = {
+  bufferMinutes: 30,
+  enabled: true,
+};
+
+// ── Helpers ───────────────────────────────────────────
+
+function reviveDates(json: string): Event[] {
+  try {
+    const parsed = JSON.parse(json) as Array<Event & { eventTime: string }>;
+    return parsed.map((e) => ({ ...e, eventTime: new Date(e.eventTime) }));
+  } catch {
+    return [];
+  }
+}
+
+// ── Events ────────────────────────────────────────────
+
+export async function loadEvents(): Promise<Event[]> {
+  const json = await AsyncStorage.getItem(EVENTS_KEY);
+  return json ? reviveDates(json) : [];
+}
+
+export async function saveEvents(events: Event[]): Promise<void> {
+  const json = JSON.stringify(events);
+  await AsyncStorage.setItem(EVENTS_KEY, json);
+}
+
+export async function addEvent(event: Event): Promise<void> {
+  const events = await loadEvents();
+  events.push(event);
+  await saveEvents(events);
+}
+
+export async function removeEvent(id: string, onDone?: () => void): Promise<void> {
+  const events = await loadEvents();
+  const filtered = events.filter((e) => e.id !== id);
+  await saveEvents(filtered);
+  onDone?.();
+}
+
+// ── Origin Station ────────────────────────────────────
+
+export async function loadOriginStation(): Promise<Station | null> {
+  const json = await AsyncStorage.getItem(ORIGIN_KEY);
+  return json ? JSON.parse(json) : null;
+}
+
+export async function saveOriginStation(station: Station): Promise<void> {
+  const json = JSON.stringify(station);
+  await AsyncStorage.setItem(ORIGIN_KEY, json);
+}
+
+// ── Notification Settings ─────────────────────────────
+
+export async function loadNotificationSettings(): Promise<ReminderSettings> {
+  const json = await AsyncStorage.getItem(NOTIFICATIONS_KEY);
+  return json ? JSON.parse(json) : DEFAULT_NOTIFICATION_SETTINGS;
+}
+
+export async function saveNotificationSettings(
+  settings: ReminderSettings,
+): Promise<void> {
+  const json = JSON.stringify(settings);
+  await AsyncStorage.setItem(NOTIFICATIONS_KEY, json);
+}