Bump to Node 22.15.1

[JustinGrote]

Prerequisites

• [x] I have written a descriptive issue title.
• [x] I have searched all issues to ensure it has not already been reported.

Summary

VSCode v1.101 bumps the engine to 22.15.1 from node 20 so we can follow suit in the extension.

There are some notable features we can take advantage of:

• Fetch API is now stable in Node.js 21, so we can remove node-fetch dependency
• More testing and integration is now stable that was previously experimental
• Websocket support (probably no need to switch from named pipes ATM)

Proposed Design

No response