fix: profile select back button bypass

close #737

lib/screens/profile/profile_switch_screen.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
 import 'package:material_symbols_icons/symbols.dart';
 import 'package:provider/provider.dart';
 import '../../models/plex_home_user.dart';
@@ -37,6 +38,11 @@ class _ProfileSwitchScreenState extends State<ProfileSwitchScreen> {
 
     return PopScope(
       canPop: !widget.requireSelection || _allowPop,
+      onPopInvokedWithResult: (didPop, _) {
+        if (!didPop && widget.requireSelection) {
+          SystemNavigator.pop();
+        }
+      },
       child: Consumer<UserProfileProvider>(
         builder: (context, userProvider, child) {
           final users = userProvider.home?.users ?? [];
@@ -44,6 +50,7 @@ class _ProfileSwitchScreenState extends State<ProfileSwitchScreen> {
           return FocusedScrollScaffold(
             title: Text(t.screens.switchProfile),
             automaticallyImplyLeading: !widget.requireSelection,
+            onBackPressed: widget.requireSelection ? () => SystemNavigator.pop() : null,
             slivers: [
               if (userProvider.isLoading)
                 const SliverFillRemaining(child: Center(child: CircularProgressIndicator()))

lib/widgets/focused_scroll_scaffold.dart

@@ -33,6 +33,11 @@ class FocusedScrollScaffold extends StatefulWidget {
   /// Defaults to true.
   final bool automaticallyImplyLeading;
 
+  /// Optional override for the back key handler.
+  /// When set, this callback is invoked instead of the default
+  /// [handleBackKeyNavigation] (which pops the current route).
+  final VoidCallback? onBackPressed;
+
   const FocusedScrollScaffold({
     super.key,
     required this.title,
@@ -40,6 +45,7 @@ class FocusedScrollScaffold extends StatefulWidget {
     this.actions,
     this.pinned = true,
     this.automaticallyImplyLeading = true,
+    this.onBackPressed,
   });
 
   @override
@@ -75,7 +81,12 @@ class _FocusedScrollScaffoldState extends State<FocusedScrollScaffold> {
 
     return Focus(
       canRequestFocus: false,
-      onKeyEvent: (_, event) => handleBackKeyNavigation(context, event),
+      onKeyEvent: (_, event) {
+        if (widget.onBackPressed != null) {
+          return handleBackKeyAction(event, widget.onBackPressed!);
+        }
+        return handleBackKeyNavigation(context, event);
+      },
       child: FocusScope(
         node: _scopeNode,
         child: Scaffold(