Caret position change event support

[Taitava]

Discussed in https://github.com/Taitava/obsidian-shellcommands/discussions/284

• [x] Implement the thing.
• [x] Add lineOrColumn setting for selecting whether the event triggers for line number changes, column number changes or both.
• [x] Write documentation.
• [ ] Write tests.
• [x] Write to CHANGELOG.md.

[Taitava]

The draft version of this was accidentally released in 0.20.0

There's now a Caret moved in editor event toggleable in the settings, but I have bad news: It doesn't work. If you enable it, it just does nothing.

I must have mixed up Git branches somehow, as I didn't mean to publish this non-working stuff yet. I'll release a fix later that removes this event from the UI, or at least adds a text that it doesn't work.