v1.9: fix Android 16 status loss, bigger widget icons/fonts, security fixes

Android 16 bug: EncryptedSharedPreferences threw on ANY exception (Keystore
busy during screen-lock/BG wakeup) and the code deleted the encrypted prefs
file on any failure, permanently erasing session cookies. Now only
KeyPermanentlyInvalidatedException (biometric/PIN change) triggers delete;
transient failures preserve the file for the next session.

Also prevents saving cookies to plain-text fallback prefs if encrypted prefs
are unavailable.

WorkManager periodic (15 min, requires network) added alongside AlarmManager
as a Doze-mode backup for Android 16, where inexact alarms can be batched up
to 75 min.

UI: sync icon 24→32dp (large widget), 20→28dp (small); reset-time font
9→11sp (large), 8→10sp (small).

Security:
- All Log.d response-body and URL-bearing logs gated behind BuildConfig.DEBUG
- Cookie header value stripped of CRLF to prevent HTTP header injection
- LoginActivity coroutine migrated from bare CoroutineScope to lifecycleScope
- Widget removed from keyguard (lock-screen) category — usage data is sensitive

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/src/main/java/me/khodak/claudeusage/UsageUpdateWorker.kt

@@ -14,6 +14,7 @@ import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import me.khodak.claudeusage.data.PreferencesManager
+import java.util.concurrent.TimeUnit
 
 class UsageUpdateWorker(
     private val context: Context,
@@ -77,21 +78,39 @@ class UsageUpdateWorker(
 
     companion object {
         private const val WORK_ONE_SHOT = "claude_oneshot"
+        private const val WORK_PERIODIC = "claude_periodic"
         private const val ALARM_CODE = 1001
         private const val INTERVAL_MS = 5 * 60 * 1000L
 
         fun schedulePeriodicRefresh(context: Context) {
+            // 5-min alarm for fast updates when the device is active/awake
             val am = context.getSystemService(Context.ALARM_SERVICE) as AlarmManager
             am.setAndAllowWhileIdle(
                 AlarmManager.ELAPSED_REALTIME_WAKEUP,
                 SystemClock.elapsedRealtime() + INTERVAL_MS,
                 alarmIntent(context)
             )
+            // WorkManager periodic as a Doze/background backup (Android 16 reliability).
+            // WorkManager uses JobScheduler which survives Doze; AlarmManager may be batched
+            // up to 75 min in Doze mode. KEEP = don't reset the 15-min timer on every alarm.
+            WorkManager.getInstance(context).enqueueUniquePeriodicWork(
+                WORK_PERIODIC,
+                ExistingPeriodicWorkPolicy.KEEP,
+                PeriodicWorkRequestBuilder<UsageUpdateWorker>(15, TimeUnit.MINUTES)
+                    .setConstraints(
+                        Constraints.Builder()
+                            .setRequiredNetworkType(NetworkType.CONNECTED)
+                            .build()
+                    )
+                    .build()
+            )
         }
 
-        fun cancelPeriodicRefresh(context: Context) =
+        fun cancelPeriodicRefresh(context: Context) {
             (context.getSystemService(Context.ALARM_SERVICE) as AlarmManager)
                 .cancel(alarmIntent(context))
+            WorkManager.getInstance(context).cancelUniqueWork(WORK_PERIODIC)
+        }
 
         fun triggerImmediateRefresh(context: Context) {
             WorkManager.getInstance(context).enqueueUniqueWork(