Update /clear' to use Handler`

Builds the message in the help handler and then uses it after clearing chat.

packages/jupyter-ai/jupyter_ai/chat_handlers/clear.py

@@ -1,9 +1,7 @@
 from typing import List
-
 from jupyter_ai.models import ChatMessage, ClearMessage
-
 from .base import BaseChatHandler, SlashCommandRoutingType
-
+from jupyter_ai.chat_handlers.help import build_help_message
 
 class ClearChatHandler(BaseChatHandler):
     """Clear the chat panel and show the help menu"""
@@ -19,15 +17,20 @@ def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
 
     async def process_message(self, _):
-        tmp_chat_history = self._chat_history[0]
-        self._chat_history.clear()
         for handler in self._root_chat_handlers.values():
             if not handler:
                 continue
 
+            # Clear chat 
             handler.broadcast_message(ClearMessage())
+            self._chat_history.clear()
 
-            self._chat_history = [tmp_chat_history]
-            self.reply(tmp_chat_history.body)
+            # Build /help message and reinstate it in chat
+            chat_handlers = handler.chat_handlers
+            persona = self.config_manager.persona
+            lm_provider = self.config_manager.lm_provider
+            unsupported_slash_commands = (lm_provider.unsupported_slash_commands if lm_provider else set())
+            msg = build_help_message(chat_handlers, persona, unsupported_slash_commands)
+            self.reply(msg.body)
 
-            break
+            break