feat: Enable direct chat initiation from agent network, improve GIF rendering in chat, and fix message order and webview authentication.

lib/features/messaging/presentation/providers/messaging_provider.dart

@@ -221,11 +221,14 @@ class MessagingNotifier extends StateNotifier<MessagingState> {
         page: nextPage,
       );
 
-      final newMessages = result.messages;
+      // API returns chronological order (oldest first), but our ListView is
+      // reverse: true so we need newest-first order (index 0 = newest).
+      final newMessages = result.messages.reversed.toList();
       final paginationInfo = result.pagination;
 
       final existingMessages =
           loadMore ? (state.messages[conversationId] ?? []) : <ChatMessage>[];
+      // When loading more (older messages), append to end (older = higher index)
       final mergedMessages =
           loadMore ? [...existingMessages, ...newMessages] : newMessages;
 
@@ -404,6 +407,36 @@ class MessagingNotifier extends StateNotifier<MessagingState> {
       return null;
     }
   }
+
+  Future<String?> startConversationWithUser(String userId) async {
+    if (!mounted) return null;
+    state = state.copyWith(isLoadingConversations: true, clearError: true);
+    try {
+      final conversation =
+          await _repository.startConversationWithUser(userId);
+
+      if (!mounted) return conversation.id;
+
+      final exists = state.conversations.any((c) => c.id == conversation.id);
+      final updatedConversations = exists
+          ? state.conversations
+          : [conversation, ...state.conversations];
+
+      state = state.copyWith(
+        conversations: updatedConversations,
+        isLoadingConversations: false,
+      );
+      return conversation.id;
+    } catch (_) {
+      if (mounted) {
+        state = state.copyWith(
+          isLoadingConversations: false,
+          error: 'Failed to start conversation',
+        );
+      }
+      return null;
+    }
+  }
 }
 
 final messagingProvider =