Fixed broken gradio code

- Fixed improper `last_input_token_count` usage before init.
- Added deps error handler

Gradio_UI.py

@@ -140,17 +140,14 @@ def stream_to_gradio(
     total_output_tokens = 0
 
     for step_log in agent.run(task, stream=True, reset=reset_agent_memory, additional_args=additional_args):
-        # Track tokens if model provides them
-        if hasattr(agent.model, "last_input_token_count"):
-            total_input_tokens += agent.model.last_input_token_count
-            total_output_tokens += agent.model.last_output_token_count
+        if hasattr(agent.model, "last_input_token_count") and agent.model.last_input_token_count is not None:
+            total_input_tokens += agent.model.last_input_token_count or 0
+            total_output_tokens += getattr(agent.model, "last_output_token_count", 0) or 0
             if isinstance(step_log, ActionStep):
                 step_log.input_token_count = agent.model.last_input_token_count
-                step_log.output_token_count = agent.model.last_output_token_count
+                step_log.output_token_count = getattr(agent.model, "last_output_token_count", 0)
 
-        for message in pull_messages_from_step(
-            step_log,
-        ):
+        for message in pull_messages_from_step(step_log):
             yield message
 
     final_answer = step_log  # Last log is the run's final_answer
@@ -191,13 +188,18 @@ class GradioUI:
 
     def interact_with_agent(self, prompt, messages):
         import gradio as gr
-
-        messages.append(gr.ChatMessage(role="user", content=prompt))
-        yield messages
-        for msg in stream_to_gradio(self.agent, task=prompt, reset_agent_memory=False):
-            messages.append(msg)
+    
+        try:
+            messages.append(gr.ChatMessage(role="user", content=prompt))
+            yield messages
+            for msg in stream_to_gradio(self.agent, task=prompt, reset_agent_memory=False):
+                messages.append(msg)
+                yield messages
+            yield messages
+        except Exception as e:
+            error_message = f"Error: {str(e)}\nPlease try again or contact support if the issue persists."
+            messages.append(gr.ChatMessage(role="assistant", content=error_message))
             yield messages
-        yield messages
 
     def upload_file(
         self,