Windows - Desktop GUI - Git bash fork, powershell and cmd fixes

[burgercrisis]

I found, fixed, tested, and confirmed several issues related to Git bash fork, powershell and cmd. Previously many command calls would fail, making the agent pretty useless at very many tasks on Windows, at least on Desktop. Not sure if it was an issue on TUI/CLI as I am... one of those guys. There are still some issues I will be resolving, but I figured I should PR this batch.

Unfortunately there are now some merge conflicts but I hey that probably happens every few hours some days

Issue
Add Git cmd and MinGW paths to git-env.ts	100% dank now
Fix stream reading race condition	100% dank now
Remove duplicate abort listeners from bash.ts	100% dank now
Add stream draining to prompt.ts	100% dank now
Fix newString undefined bug	100% dank now
Fix desktop race condition	100% dank now
Add shell bypass to prompt.ts	100% dank now
Add unique match identification	100% dank now
Fix Unicode character matching	100% dank now
Fix multi-line patterns	100% dank now