Assess Neovim 0.12 nightly Compatibility

[alex-courtis]

Neovim 0.11.0 has been released.

0.12 nightly contains many changes.

Test and assess comaptibility, scoping work required.

[alex-courtis]

No apparent issues on basic usage.

No API issues reported by nightly CI.

I'll close and use nightly as my daily driver.