Refs: https://github.com/github/copilot/issues/13043

Todo:

• convert Copilot status contribution to language status indicator
• convert Copilot quota indication into a full status indicator
• 🏃 remove 🤖 entry from status bar from completions extension (March 7th)
• 🏃 provide core Codicons for what Completions needs (https://github.com/github/copilot/issues/15350)
• 🏃 explore a more permanent Copilot status indicator as entry point to settings, quota, chat and setup

//cc @bamurtaugh