fix: AI chat loading indicator and auto-refresh tasks

- Add animated typing indicator (bouncing dots) when AI is processing
- Show "Thinking..." status in chat header while processing
- Add translations for AI chat (en/de): title, welcome, placeholder, thinking, error
- Auto-refresh tasks, labels, and user data after AI response
- Disable input field while AI is processing
- Fix translation keys to use ai.chat.* namespace

client/src/pages/AiChatPage.tsx

@@ -260,14 +260,10 @@ export default function AiChatPage() {
         onSuccess: (userMessage, vars, context) => { // Returns USER message now
             queryClient.invalidateQueries({ queryKey: ["/api/ai/conversations", vars.conversationId, "messages"] });
             queryClient.invalidateQueries({ queryKey: ["/api/ai/conversations"] });
-
-            // Note: We don't get the bot message here anymore immediately.
-            // The polling (refetchInterval) will pick it up when ready.
-
-            // Auto-title if this was the first exchange? 
-            // We can still do it, but we won't have the bot response content yet for the title gen.
-            // Maybe title gen should happen on backend in the background too?
-            // For now, let's skip auto-title on first msg OR move it to backend trigger.
+            // Refresh tasks and labels in case AI created/modified them
+            queryClient.invalidateQueries({ queryKey: ['/api/tasks'] });
+            queryClient.invalidateQueries({ queryKey: ['/api/labels'] });
+            queryClient.invalidateQueries({ queryKey: ['/api/user'] });
         },
     });