implemented a customizable chat background system with support for patterns, solid colors, and gallery images; added a dedicated settings page with live preview and adjustable blur/dim effects, updated the image cropper to support flexible aspect ratios for wallpapers, and integrated file cleanup logic during account logout.

lib/widget/avatar_crop_page.dart

@@ -5,12 +5,20 @@ import 'package:flutter/material.dart';
 
 import 'app_progress_indicator.dart';
 
-/// Full-screen 1:1 cropper. Pure-Flutter so it inherits the app theme and
+/// Full-screen cropper. Pure-Flutter so it inherits the app theme and
 /// MediaQuery insets (no UCrop / native Activity needed). Returns the
 /// cropped JPEG/PNG bytes via Navigator pop, or `null` on cancel.
+///
+/// Defaults to a 1:1 crop (avatar use). Pass [aspectRatio] to override, or
+/// `null` for a free-form crop (e.g. chat backgrounds).
 class AvatarCropPage extends StatefulWidget {
   final Uint8List imageBytes;
-  const AvatarCropPage({required this.imageBytes, super.key});
+  final double? aspectRatio;
+  const AvatarCropPage({
+    required this.imageBytes,
+    this.aspectRatio = 1.0,
+    super.key,
+  });
 
   @override
   State<AvatarCropPage> createState() => _AvatarCropPageState();
@@ -60,7 +68,7 @@ class _AvatarCropPageState extends State<AvatarCropPage> {
         child: Crop(
           image: widget.imageBytes,
           controller: _controller,
-          aspectRatio: 1.0,
+          aspectRatio: widget.aspectRatio,
           interactive: false,
           baseColor: theme.colorScheme.surface,
           maskColor: Colors.black.withValues(alpha: 0.6),