Users should be able to link to other entries #9

Not really sure how to best reflect this in a TUI. Might be useful for searching?

Say [[[note]]] is how notes are referenced.

There are a few things to decide:

what goes in the brackets.
How does it get linked.

For 1, I think we should support a few different ways, and we'll start with id. For example

This references the first note [[[id:1]]]

For 2, we should parse the text for all [[[note]]]. References get created in a table that maps a note id to another note id. When a note gets updated, we need to look for all the notes that it references and update accordingly.

For example, the note could initially look like this:

This references the first note [[[id:1]]], and this the second [[[id:2]]]

The table would look like:

source|target
3     | 1
3     | 2

Say an update is made:

This references the first note [[[id:1]]]

The table should be updated to reflect the deletion of that note

source|target
3     | 1
3     | 2