add sqlite

mobile/services/db/repositories/preferences.ts

@@ -0,0 +1,33 @@
+import { getDatabase } from '../client';
+import { PREFERENCES_KEY } from '../schema';
+import type { UserPreferences } from '../types';
+
+const DEFAULT_PREFERENCES: UserPreferences = {
+  syncMode: 'full',
+};
+
+export async function saveUserPreferences(preferences: UserPreferences): Promise<void> {
+  const db = await getDatabase();
+  await db.runAsync(
+    `INSERT INTO user_preferences ("key", "value", updated_at) VALUES (?, ?, ?)
+     ON CONFLICT("key") DO UPDATE SET "value" = excluded."value", updated_at = excluded.updated_at`,
+    PREFERENCES_KEY,
+    JSON.stringify(preferences),
+    Date.now(),
+  );
+}
+
+export async function getUserPreferences(): Promise<UserPreferences> {
+  const db = await getDatabase();
+  const row = await db.getFirstAsync<{ value: string }>(
+    'SELECT "value" FROM user_preferences WHERE "key" = ?',
+    PREFERENCES_KEY,
+  );
+  if (!row) return DEFAULT_PREFERENCES;
+
+  try {
+    return { ...DEFAULT_PREFERENCES, ...JSON.parse(row.value) } satisfies UserPreferences;
+  } catch {
+    return DEFAULT_PREFERENCES;
+  }
+}