Add development/vimwiki-gap.md, a checkbox-tracked audit of where nuwiki
diverges from upstream vimwiki across configuration options, Ex-commands,
and key mappings. Items are prioritised P1–P3 with a fix site cited on
each, plus an "intentional divergences" section so the LSP-rearchitected
choices aren't re-flagged in future audits.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
