fix: client tool response message

[louisjoecodes]

Fixes client tool message response:

• Server expects result not response
• Server expects a response from client_tool_result in all case. If the user defines a client tool like this:

     clientTools: {
                triggerBrowserAlert: async (paramaters: {
                    message: string
                }) => {
                    alert(paramaters.message)
                }

it would cause the conversation to crash and end. Therefore we now have a default response of Client tool execution successful.