Auto sync setting, pretty notifications, background permissions,

reliable alarm scheduling

Auto sync:
- Configurable interval: 1/2/5/10/15/30/60 min (default 5)
- MemoRepository.syncIntervalMinutes updated live from DataStore
- Setting shown under "memos" section in settings

Notifications by priority:
- p1: 🔴 alarm sound, long vibration, wakes screen, bypasses DND
- p2: 🟠 notification sound, medium vibration, heads-up
- p3: 🔵 notification sound, short vibration
- none: silent, no vibration
- BigTextStyle with priority tag, colored accent bar
- 4 separate Android notification channels

Background reliability:
- FOREGROUND_SERVICE, WAKE_LOCK, REQUEST_IGNORE_BATTERY_OPTIMIZATIONS
- Battery optimization exemption requested on first launch
- DirectAlarmScheduler: schedules alarms directly from app process
  using live Room data (bypasses WorkManager DB sync issue)
- onContentChanged fires direct scheduling on every memo create/update
- TaskReminderReceiver moved to androidApp module for reliable
  cold-start instantiation
- WorkManager kept as 15-min backup for server-side changes

123 tests passing.

Co-Authored-By: Claude Opus 4.6 (1M context)

Signed-off-by: Avinal Kumar <avinal.xlvii@gmail.com>

androidApp/src/main/AndroidManifest.xml

@@ -6,6 +6,9 @@
     <uses-permission android:name="android.permission.SCHEDULE_EXACT_ALARM" />
     <uses-permission android:name="android.permission.USE_EXACT_ALARM" />
     <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
+    <uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS" />
+    <uses-permission android:name="android.permission.WAKE_LOCK" />
 
     <application
         android:allowBackup="true"
@@ -28,7 +31,7 @@
         </activity>
 
         <receiver
-            android:name="com.avinal.memos.notifications.TaskAlarmReceiver"
+            android:name=".TaskReminderReceiver"
             android:exported="false" />
 
         <receiver

androidApp/src/main/kotlin/com/avinal/memos/MainActivity.kt

@@ -28,8 +28,9 @@ class MainActivity : ComponentActivity() {
         deps.initialize()
         com.avinal.memos.util.appContext = applicationContext
 
-        TaskNotificationManager.createChannel(this)
+        TaskNotificationManager.createChannels(this)
         requestNotificationPermission()
+        requestBatteryOptimizationExemption()
         scheduleTaskChecker(applicationContext)
 
         enableEdgeToEdge()
@@ -49,4 +50,16 @@ class MainActivity : ComponentActivity() {
             }
         }
     }
+
+    private fun requestBatteryOptimizationExemption() {
+        val pm = getSystemService(android.os.PowerManager::class.java)
+        if (!pm.isIgnoringBatteryOptimizations(packageName)) {
+            try {
+                startActivity(android.content.Intent(
+                    android.provider.Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS,
+                    android.net.Uri.parse("package:$packageName")
+                ))
+            } catch (_: Exception) {}
+        }
+    }
 }

androidApp/src/main/kotlin/com/avinal/memos/TaskReminderReceiver.kt

@@ -0,0 +1,26 @@
+package com.avinal.memos
+
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import com.avinal.memos.notifications.TaskNotificationManager
+
+class TaskReminderReceiver : BroadcastReceiver() {
+    override fun onReceive(context: Context, intent: Intent) {
+        android.util.Log.d("TaskReminderReceiver", "onReceive fired!")
+        val taskText = intent.getStringExtra("task_text") ?: "Task reminder"
+        val dueLabel = intent.getStringExtra("due_label") ?: "due"
+        val notificationId = intent.getIntExtra("notification_id", 0)
+        val priority = intent.getIntExtra("priority", 0)
+
+        android.util.Log.d("TaskReminderReceiver", "Showing: $taskText - $dueLabel (p=$priority, id=$notificationId)")
+        TaskNotificationManager.createChannels(context)
+        TaskNotificationManager.showTaskNotification(
+            context = context,
+            notificationId = notificationId,
+            taskText = taskText,
+            dueLabel = dueLabel,
+            priority = priority,
+        )
+    }
+}