fix: Pip servers handle config changes gracefully

[bmingles]

• Pip servers now support a larger range of ports
• Configured servers now reserve ports so pip servers won't touch them
• If configuration changes such that a running pip server becomes reserved by config, the pip server will be shut down
• Keep server state for running pip servers on config change so that generated PSKs can continue to be used

Testing
I used a configuration targetting the first few ports starting at 10000

Initial config (servers all commented out)

"deephaven.coreServers": [
  // "http://localhost:10000/",
  // "http://localhost:10001/",
  // "http://localhost:10002/",

Pip server port becomes reserved via config change

• Start a pip server (should start on port 10000)
• Modify config by uncommenting "http://localhost:10000/"
• Pip server should automatically stop. localhost:10000 should be listed under "Stopped" and no longer under "Managed"

Start server outside of extension

• Start a server on port 10000 (outside of extension)
• Refreshing server panel should show it as running and allow connection

Arbitrary config change

• Start a pip server
• Make a config change that doesn't affect the port of the running server
• Pip server should remain connected and usable

resolves #137

[github-actions]

End-to-end Test Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Pending ⏳	Other ❓	Flaky 🍂	Duration ⏱️
6	6	0	0	0	0	0	04:59:49

A ctrf plugin

Detailed Test Results

Name	Status	ms	Flaky 🍂
should default to the correct settings	passed ✅	1735
should return custom settings: Empty configs	passed ✅	293
should return custom settings: Populated configs	passed ✅	191
should be able to load VSCode	passed ✅	1038
should only be visible when a supported file type is active: test.groovy	passed ✅	2783
should only be visible when a supported file type is active: test.py	passed ✅	1012

A ctrf plugin

Failed Test Summary

No failed tests ✨

Flaky Test Summary

No flaky tests detected. ✨

[mofojed]

Why stop at 10050? Why not like 10999?

[bmingles]

It was arbitrary. Figured 50 was even higher than system resources would probably allow