Add biometric lock and rate limit handling

Biometric lock: opt-in Face ID/Touch ID/fingerprint app lock with toggle
in ProfileScreen. Locks on background, requires auth on foreground return.
Platform implementations: BiometricPrompt (Android), LAContext (iOS).

Rate limit: 429 responses parsed with Retry-After header, user-friendly
error messages in all 10 locales, retry plugin respects 429.
ErrorMessageParser updated for both iOS Swift and KMM.

composeApp/src/iosMain/kotlin/com/tt/honeyDue/MainViewController.kt

@@ -5,6 +5,8 @@ import com.tt.honeyDue.storage.TokenManager
 import com.tt.honeyDue.storage.TokenStorage
 import com.tt.honeyDue.storage.TaskCacheManager
 import com.tt.honeyDue.storage.TaskCacheStorage
+import com.tt.honeyDue.storage.BiometricPreference
+import com.tt.honeyDue.storage.BiometricPreferenceManager
 import com.tt.honeyDue.storage.ThemeStorage
 import com.tt.honeyDue.storage.ThemeStorageManager
 import com.tt.honeyDue.ui.theme.ThemeManager
@@ -20,5 +22,8 @@ fun MainViewController() = ComposeUIViewController {
     ThemeStorage.initialize(ThemeStorageManager.getInstance())
     ThemeManager.initialize()
 
+    // Initialize BiometricPreference storage
+    BiometricPreference.initialize(BiometricPreferenceManager.getInstance())
+
     App()
 }