[Feature]: Allow Emoji Selection for Copilot and Chat Icons

[JosephScript]

Problem Description
Currently, the only option for adding a chat image is to provide a remote PNG URL when creating or editing "My Copilots". This limits customization and requires users to find and host images. Additionally there is now way to retroactively change the Chat icons themselves after the fact to be different.

Proposed Solution
Implement the ability to select an emoji for both Copilots and Chat icons. This would allow for quick, fun, and diverse personalization without needing external image URLs.

Detailed Steps/Implementation:

• My Copilots: Add a button/option next to the image URL input when creating/editing a Copilot that opens an emoji selector.
• Chat List Icons: Allow users to change chat icons using the same emoji selector approach as above. This would likely be accessible through the edit menu option for individual chats in the chat list.

Additional Context
Providing an emoji selector would:

• Simplify the icon selection process
• Offer a more user-friendly experience
• Allow for more creative and diverse icon choices.
• Remove the need to host image files

This feature would be a small, yet valuable addition that would enhance the visual customizability of Chatbox.