avatar (#14440)

* avatar

* refactor avatar display: unify rendering and resolve at use time

  - Extract buildAvatarWidget() in common.dart to share avatar rendering
    logic across desktop settings, desktop CM and mobile CM
  - Add resolve_avatar_url() in Rust, exposed via FFI (SyncReturn),
    to resolve relative avatar paths (e.g. "/avatar/xxx") to absolute URLs
  - Store avatar as-is in local config, only resolve when displaying
    (settings page) or sending (LoginRequest)
  - Resolve avatar in LoginRequest before sending to remote peer
  - Add error handling for network image load failures
  - Guard against empty client.name[0] crash
  - Show avatar in mobile settings page account tile

Signed-off-by: 21pages <sunboeasy@gmail.com>

* web: implement mainResolveAvatarUrl via js getByName

Signed-off-by: 21pages <sunboeasy@gmail.com>

* increase ipc Data enum size limit to 120 bytes

Signed-off-by: 21pages <sunboeasy@gmail.com>

---------

Signed-off-by: 21pages <sunboeasy@gmail.com>
Co-authored-by: 21pages <sunboeasy@gmail.com>

flutter/lib/mobile/pages/server_page.dart

@@ -841,13 +841,7 @@ class ClientInfo extends StatelessWidget {
                   flex: -1,
                   child: Padding(
                       padding: const EdgeInsets.only(right: 12),
-                      child: CircleAvatar(
-                          backgroundColor: str2color(
-                              client.name,
-                              Theme.of(context).brightness == Brightness.light
-                                  ? 255
-                                  : 150),
-                          child: Text(client.name[0])))),
+                      child: _buildAvatar(context))),
               Expanded(
                   child: Column(
                       crossAxisAlignment: CrossAxisAlignment.start,
@@ -860,6 +854,20 @@ class ClientInfo extends StatelessWidget {
           ),
         ]));
   }
+
+  Widget _buildAvatar(BuildContext context) {
+    final fallback = CircleAvatar(
+      backgroundColor: str2color(
+          client.name,
+          Theme.of(context).brightness == Brightness.light ? 255 : 150),
+      child: Text(client.name.isNotEmpty ? client.name[0] : '?'),
+    );
+    return buildAvatarWidget(
+      avatar: client.avatar,
+      size: 40,
+      fallback: fallback,
+    )!;
+  }
 }
 
 void androidChannelInit() {

flutter/lib/mobile/pages/settings_page.dart

@@ -689,7 +689,15 @@ class _SettingsState extends State<SettingsPage> with WidgetsBindingObserver {
                 title: Obx(() => Text(gFFI.userModel.userName.value.isEmpty
                     ? translate('Login')
                     : '${translate('Logout')} (${gFFI.userModel.accountLabelWithHandle})')),
-                leading: Icon(Icons.person),
+                leading: Obx(() {
+                  final avatar = bind.mainResolveAvatarUrl(
+                      avatar: gFFI.userModel.avatar.value);
+                  return buildAvatarWidget(
+                        avatar: avatar,
+                        size: 40,
+                      ) ??
+                      Icon(Icons.person);
+                }),
                 onPressed: (context) {
                   if (gFFI.userModel.userName.value.isEmpty) {
                     loginDialog();