implemented avatar management for user profiles and chat rooms, including 1:1 cropping, integrated OCS and Spreed avatar APIs, added cache invalidation logic, and updated the account settings view to display user info and profile pictures.

lib/view/pages/talk/details/chat_info.dart

@@ -6,7 +6,9 @@ import '../../../../api/marianumcloud/talk/get_participants/get_participants_cac
 import '../../../../api/marianumcloud/talk/get_participants/get_participants_response.dart';
 import '../../../../api/marianumcloud/talk/room/get_room_response.dart';
 import '../../../../state/app/modules/chat_list/bloc/chat_list_bloc.dart';
+import '../../../../widget/app_progress_indicator.dart';
 import '../../../../widget/async_action_button.dart';
+import '../../../../widget/avatar_actions_sheet.dart';
 import '../../../../widget/confirm_dialog.dart';
 import '../../../../widget/large_profile_picture_view.dart';
 import '../../../../widget/loading_spinner.dart';
@@ -25,6 +27,8 @@ class ChatInfo extends StatefulWidget {
 class _ChatInfoState extends State<ChatInfo> {
   GetParticipantsResponse? participants;
   late bool _isFavorite;
+  int _avatarVersion = 0;
+  bool _avatarBusy = false;
 
   @override
   void initState() {
@@ -66,28 +70,101 @@ class _ChatInfoState extends State<ChatInfo> {
     if (closed == true && mounted) Navigator.of(context).pop();
   }
 
+  // Spreed's POST /room/{token}/avatar requires moderator rights and rejects
+  // 1:1, changelog and note-to-self rooms server-side. Mirror that here so
+  // the edit affordance only shows when the upload would actually succeed.
+  bool _canEditAvatar() {
+    final room = widget.room;
+    const editableTypes = {
+      GetRoomResponseObjectConversationType.group,
+      GetRoomResponseObjectConversationType.public,
+    };
+    if (!editableTypes.contains(room.type)) return false;
+    // Owner=1, Moderator=2, GuestModerator=6.
+    return room.participantType == 1 ||
+        room.participantType == 2 ||
+        room.participantType == 6;
+  }
+
+  Future<void> _editAvatar() async {
+    final result = await showAvatarActionsSheet(context, allowRemove: true);
+    if (result == null || !mounted) return;
+
+    if (result is AvatarRemoveResult) {
+      var confirmed = false;
+      await showDialog<void>(
+        context: context,
+        builder: (_) => ConfirmDialog(
+          title: 'Gruppenbild entfernen',
+          content: 'Möchtest du das Gruppenbild wirklich entfernen?',
+          confirmButton: 'Entfernen',
+          onConfirm: () => confirmed = true,
+        ),
+      );
+      if (!confirmed || !mounted) return;
+    }
+
+    setState(() => _avatarBusy = true);
+    final ok = await runWithErrorDialog(context, () async {
+      if (result is AvatarUploadResult) {
+        await SetRoomAvatar(widget.room.token, result.bytes).run();
+      } else {
+        await DeleteRoomAvatar(widget.room.token).run();
+      }
+    });
+    if (!mounted) return;
+    setState(() => _avatarBusy = false);
+    if (!ok) return;
+
+    invalidateAvatarCache(id: widget.room.token, isGroup: true);
+    setState(() => _avatarVersion++);
+    _refreshList();
+  }
+
   @override
   Widget build(BuildContext context) {
     var isGroup =
         widget.room.type != GetRoomResponseObjectConversationType.oneToOne;
+    final canEdit = _canEditAvatar();
     return Scaffold(
       appBar: AppBar(title: Text(widget.room.displayName)),
       body: ListView(
         children: [
           const SizedBox(height: 30),
           Center(
-            child: GestureDetector(
-              child: UserAvatar(
-                id: isGroup ? widget.room.token : widget.room.name,
-                isGroup: isGroup,
-                size: 80,
-              ),
-              onTap: () => TalkNavigator.pushSplitView(
-                context,
-                LargeProfilePictureView(
-                  id: isGroup ? widget.room.token : widget.room.name,
-                  isGroup: isGroup,
-                ),
+            child: SizedBox(
+              width: 180,
+              height: 180,
+              child: Stack(
+                clipBehavior: Clip.none,
+                children: [
+                  Center(
+                    child: GestureDetector(
+                      child: UserAvatar(
+                        key: ValueKey(_avatarVersion),
+                        id: isGroup ? widget.room.token : widget.room.name,
+                        isGroup: isGroup,
+                        size: 80,
+                      ),
+                      onTap: () => TalkNavigator.pushSplitView(
+                        context,
+                        LargeProfilePictureView(
+                          id: isGroup ? widget.room.token : widget.room.name,
+                          isGroup: isGroup,
+                        ),
+                      ),
+                    ),
+                  ),
+                  if (canEdit)
+                    Positioned(
+                      right: 18,
+                      bottom: 18,
+                      child: _AvatarEditBadge(
+                        busy: _avatarBusy,
+                        onTap: _avatarBusy ? null : _editAvatar,
+                      ),
+                    ),
+                ],
               ),
             ),
           ),
@@ -153,3 +230,39 @@ class _ChatInfoState extends State<ChatInfo> {
     );
   }
 }
+
+class _AvatarEditBadge extends StatelessWidget {
+  final bool busy;
+  final VoidCallback? onTap;
+  const _AvatarEditBadge({required this.busy, required this.onTap});
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    return Material(
+      color: theme.colorScheme.primary,
+      shape: const CircleBorder(),
+      elevation: 2,
+      child: InkWell(
+        customBorder: const CircleBorder(),
+        onTap: onTap,
+        child: SizedBox(
+          width: 30,
+          height: 30,
+          child: busy
+              ? Padding(
+                  padding: const EdgeInsets.all(7),
+                  child: AppProgressIndicator.small(
+                    color: theme.colorScheme.onPrimary,
+                  ),
+                )
+              : Icon(
+                  Icons.edit,
+                  size: 15,
+                  color: theme.colorScheme.onPrimary,
+                ),
+        ),
+      ),
+    );
+  }
+}