feat(mobile): use shared native client (#25942)

* use shared client in dart

fix android

* websocket integration

platform-side headers

update comment

consistent platform check

tweak websocket handling

support streaming

* redundant logging

* fix proguard

* formatting

* handle onProgress

* support videos on ios

* inline return

* improved ios impl

* cleanup

* sync stopForegroundBackup

* voidify

* future already completed

* stream request on android

* outdated ios ws code

* use `choosePrivateKeyAlias`

* return result

* formatting

* update tests

* redundant check

* handle custom headers

* move completer outside of state

* persist auth

* dispose old socket

* use group id for cookies

* redundant headers

* cache global ref

* handle network switching

* handle basic auth

* apply custom headers immediately

* video player update

* fix

* persist url

* potential logout fix

---------

Co-authored-by: Alex <alex.tran1502@gmail.com>

mobile/lib/pages/backup/drift_backup.page.dart

@@ -96,10 +96,6 @@ class _DriftBackupPageState extends ConsumerState<DriftBackupPage> {
       await backupNotifier.startForegroundBackup(currentUser.id);
     }
 
-    Future<void> stopBackup() async {
-      await backupNotifier.stopForegroundBackup();
-    }
-
     return Scaffold(
       appBar: AppBar(
         elevation: 0,
@@ -136,9 +132,9 @@ class _DriftBackupPageState extends ConsumerState<DriftBackupPage> {
                   const Divider(),
                   BackupToggleButton(
                     onStart: () async => await startBackup(),
-                    onStop: () async {
+                    onStop: () {
                       syncSuccess = null;
-                      await stopBackup();
+                      backupNotifier.stopForegroundBackup();
                     },
                   ),
                   switch (error) {