Add copy all messages button to chatbot

[hannahblair]

Description

Adds a copy all button (via a show_copy_all_button param) similar to gr.JSON and other components. I'm curious to know if we think this should look more unique to the other copy buttons in Chatbot 🤔

Having other messages with copy buttons will look confusing, and scrolling will look terrible if users have copy buttons as well (which I've asked about in Slack)

We could use a clipboard icon:

but then we're losing out on consistency between other components.

Also, should default be true or false?

Test:

import gradio as gr

with gr.Blocks() as demo:
    gr.Chatbot(show_copy_all_button=True, show_copy_button=True, value=[["Hello World","Hey Gradio!"],["❤️","😍"],["🔥","🤗"]])

demo.launch()

Clipboard output:

user: Hello World

assistant: Hey Gradio!

user: ❤️

assistant: 😍

user: 🔥

assistant: 🤗

Closes: #7446

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[gradio-pr-bot]

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Install Gradio from this PR

pip install https://gradio-pypi-previews.s3.amazonaws.com/37141e9807203a720acfc0e4193936ec6f15cec6/gradio-4.41.0-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@37141e9807203a720acfc0e4193936ec6f15cec6#subdirectory=client/python"

Install Gradio JS Client from this PR

npm install https://gradio-npm-previews.s3.amazonaws.com/37141e9807203a720acfc0e4193936ec6f15cec6/gradio-client-1.5.0.tgz

[abidlabs]

Suggested change

	show_copy_all_button=False,
	show_copy_all_button: bool = False,

[abidlabs]

lgtm @hannahblair! tested, works great

I agree about using the same copy icon. The position of the icon is enough to signify that it copies all messages

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/chatbot	minor
@gradio/code	minor
gradio	minor

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Add copy all messages button to chatbot

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