Implement background sync for xmr using flutter_daemon (#2094)

* Implement background sync for xmr using flutter_daemon

* - initialize app config in background thread
- initializeAppConfigs without loading the wallet.

* - properly do awaited calls in methodChannel
- prevent locking main thread during background sync

* add back background sync debug page
fix issues caused by xmr wallet being view only (and read only)

* changes from review
improve starting of bgsync task

* update stopBackgroundSync, await listener functions, ensure that listener always start (call _start in constructor)

* DO-NOT-MERGE: extre verbose monero logs

* stop background service when app is being opened

* improve monitoring of background sync

* update flutter_daemon to ensure network constraint
prevent throwing errors on isBackgroundSyncEnabled
check network before syncing

* Update lib/main.dart

* revert Update main.dart [skip ci]

* continously run network check

* disable charging requirement,
fix status reporting of background sync in UI

* Refactor background sync logic, and add UI notifications for battery optimization. Updated flutter_daemon version modified build.gradle for signing config to allow testing in both release and debug modes.

* verbose monero only when requested in code.
Do not start background sync when battery optimization is on

* fix background sync mode not properly reflecting state changes

* drop unnecessary dependency

---------

Co-authored-by: Omar Hatem <omarh.ismail1@gmail.com>

android/app/build.gradle

@@ -37,7 +37,7 @@ if (appPropertiesFile.exists()) {
 }
 
 android {
-    compileSdkVersion 34
+    compileSdkVersion 35
     buildToolsVersion "34.0.0"
 
     lintOptions {
@@ -81,6 +81,9 @@ android {
 
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
+       debug {
+            signingConfig signingConfigs.release
+       }
    }
 
     ndkVersion "27.0.12077973"