Remove stale phase/spec references from code comments

Strip "Phase N", "SPEC §X.Y", and "v1.x" planning labels from comments
across the Rust crates and editor layers now that those tracking
artifacts are gone. Comments only — no logic, strings, or test names
touched.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

development/tests/test-keymaps-vim.vim

@@ -95,10 +95,10 @@ else
   call s:record(0, 'cmd.NuwikiIndex_defined', ':NuwikiIndex not registered')
 endif
 
-" ===== Documented command surface (doc/nuwiki.txt §5) =====
+" ===== Documented command surface =====
 " Every command must be reachable in BOTH the canonical :Nuwiki* form and
-" the vimwiki-compatible :Vimwiki* form. The suffixes below are the §5 list
-" minus the prefix. :NuwikiInstall is the one exception — it's a nuwiki-only
+" the vimwiki-compatible :Vimwiki* form. The suffixes below are the command
+" list minus the prefix. :NuwikiInstall is the one exception — it's a nuwiki-only
 " maintenance command with no :Vimwiki* alias, so it's checked separately.
 
 let s:both_forms = [
@@ -151,7 +151,7 @@ call s:record(
       \ 'invoke.VimwikiNextLink_jumps_to_first_link',
       \ 'col=' . col('.'))
 
-" ===== Documented mapping surface (doc §6/§7/§8) =====
+" ===== Documented mapping surface =====
 " Every documented mapping must resolve to a buffer-local mapping in the
 " mode(s) the doc lists it under. The mouse group is opt-in — the shell
 " wrapper sets g:nuwiki_mouse_mappings before the ftplugin loads.