Bing Chat (AI) Search Shortcut wót TReKiE

Adds a built-in search provider with shortcut (default is chat) to search the Bing AI Chat bot. You'll need to be granted access to the Bing AI first via www.bing.com/chat, and you may need another extension for Firefox to pretend to have the Edge user agent (there's several add-ons already listed for this).