Internal links: use a Monaco link provider

[codebykat]

This PR adds a custom LinkProvider that searches the note for simplenote:// links and linkifies them, then handles the click event by opening the linked note in the editor.

If the note ID does not refer to a note we can open, it will silently fail. I'm not sure what else it can or should do in that case.

Also adds a check to the preview component to skip links that can't be opened (i.e. the noteId isn't in our notes list), as otherwise it closes the selected note in favor of.. nothing.

[belcherj]

Could you update the PR description with more detail for posterity? Great work!

[codebykat]

Updated to address comments, and added a check in the preview component so that it also skips any links that can't be opened in the editor (rather than closing the selected note).

[belcherj]

Tested, code looks good.

[dmsnell]

Excellent work on this PR. I left a comment about making the types more convenient for you and feel free to do that and merge without a re-approval; feel free to ignore it since it's just a small convenience thing.

This was a good find allowing us to avoid the complexity of re-implementing the built-in link state machine. It's a straightforward solution.

[souljedi]

Great work! I've been waiting for something like this for years.

Would it be possible to add anchor points to the link (to jump somewhere within a note)? For example the heading titles from markdown could be used?