Issue Tracker: Refactor buffer manager

[theol0403]

Currently, external buffers are not supported, as well as switching between upper case marks and jumplist.

Issues:

• :term #476
• Improve external buffers #505
• Global marks throwing errors and not reusing existing tabs #1223
• Use VSCode document API for external buffers #1432
• BufferManager: nvim_win_set_cursor: Cursor position outside buffer #498
• vim.api.nvim_set_current_win doesn't work #1241

[ian-h-chamberlain]

@theol0403 I see there doesn't appear to be an issue for there is new readonly vscode API for external buffers. Would you like me to create one?

I started a proof-of-concept for making external buffers use the TextDocumentContentProvider API, which is what I assume this is referring to. I'm happy to work on a PR if that's the intended direction (and can discuss implementation details, design etc. on a new issue if that's the idea).

[theol0403]

@ian-h-chamberlain go for it, PRs always welcome!

[ian-h-chamberlain]

Created #1432 if you want to link it in the body of this issue