This allows you to write `buffer_snapshot.debug(ranges, value)` and it
will be displayed in the buffer (or multibuffer!) until that callsite
runs again. `ranges` can be any position (`usize`, `Anchor`, etc), any
range, or a slice or vec of those. `value` just needs a `Debug` impl.
These are stored in a mutable global for convenience, and this is only
available in debug builds.
For example, using this to visualize the captures of the brackets
Tree-sitter query:
<img width="1215" height="480" alt="image"
src="https://github.com/user-attachments/assets/c1878fc7-f6b3-4e27-949e-ecf67a7906b9"
/>
Release Notes:
- N/A
e43ad858d8