fix(client): small mapping/command-attribute parity gaps

Clean, fully-wired parity fixes (skipping the accept-but-ignore ones):

- <D-CR> (macOS Cmd+Return) → follow_link_drop, alongside <C-S-CR>, in both
  clients. Upstream binds both to VimwikiTabDropLink.
- plugin/nuwiki.vim global map block: fix the same diary collision the
  buffer-local maps had — <Leader>w<Leader>t now opens today in a new tab and
  <Leader>w<Leader>m (tomorrow) is added.
- Neovim TabIndex: add -count to NuwikiTabIndex and switch both
  Vimwiki/NuwikiTabIndex from vim.v.count (always 0 in command context) to
  <count>, so a count is actually honored.
- Converge VimwikiTableMoveColumn{Left,Right}: the Vim-branch commands now call
  the table_move_column_left/right aliases, matching the Neovim branch.
- VimwikiColorize/NuwikiColorize: -nargs=1 → -nargs=* (all four defs) for
  upstream parity; a bare :VimwikiColorize now prompts for the colour.

Docs (README + doc/nuwiki.txt) updated; mapping surfaces gain <D-CR> and
<Leader>w<Leader>m in both harnesses. vim 265+18, nvim 272, all green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

development/vimwiki-gap.md

@@ -167,13 +167,14 @@ fix site.
   Neovim. Works in Vim, coc, and Neovim (pure syntax + `:highlight`, no LSP
   needed). Covered by `colorize.conceal_hides_tags_shows_text` (both harnesses)
   and `colorize.command_conceals_immediately` (`test-keymaps-vim.vim`).
-- [ ] **`VimwikiTableMoveColumn{Left,Right}` dispatch to different backing names
-  per client** — Vim branch → `table_move_left/right`; Neovim branch →
-  `table_move_column_left/right`. Harmless today (each name exists in its own
-  impl) but a divergence to converge.
-- [ ] **`NuwikiTabIndex` lacks `-count` in the Neovim branch** (`:452`) while its
-  siblings (`VimwikiTabIndex`, `NuwikiIndex`, and the Vim-branch `NuwikiTabIndex`)
-  all carry it — `vim.v.count` is still read, so a count is honored inconsistently.
+- [x] **`VimwikiTableMoveColumn{Left,Right}` dispatch to different backing names
+  per client** — converged: the Vim-branch commands now call
+  `nuwiki#commands#table_move_column_left/right` (existing aliases over the
+  `table_move_left/right` impls), matching the Neovim branch.
+- [x] **`NuwikiTabIndex` lacks `-count` in the Neovim branch** — added `-count`;
+  also switched both Neovim `Vimwiki/NuwikiTabIndex` from `vim.v.count` (always 0
+  in command context) to `<count>`, so a `:NNuwikiTabIndex` count is now actually
+  honored.
 - [ ] **`VimwikiToggleListItem` / `Increment` / `DecrementListItem` lack
   `-range`** (both branches) vs upstream's `-range` (`:350`) — no visual-range
   checkbox toggle / symbol cycle.
@@ -189,8 +190,10 @@ fix site.
   page / tag / colour names at the `:` line is unavailable. _Fix:_
   `ftplugin/vimwiki.vim` (both branches) — VimL completers or LSP-backed.
 - [ ] **Minor command-attribute gaps** _(new)_ — `VimwikiNormalizeLink` lacks
-  upstream's `-nargs=?`; `VimwikiCheckLinks` lacks `-range`; `VimwikiColorize` is
-  `-nargs=1` vs upstream `-nargs=*`. Cosmetic.
+  upstream's `-nargs=?`; `VimwikiCheckLinks` lacks `-range`. (`VimwikiColorize`
+  `-nargs=1`→`-nargs=*` **done** — all four defs now match upstream, so a bare
+  `:VimwikiColorize` prompts for the colour.) The remaining two would be
+  accepted-but-ignored without handler work, so left open.
 
 ### Config
 - [ ] `auto_header` — auto H1-from-filename on new page (server-side).
@@ -215,14 +218,14 @@ fix site.
   all lists; upstream `ftplugin/vimwiki.vim:553,555,561`). nuwiki has the
   lowercase forms but not the uppercase-suffix aliases. Cosmetic — same effect,
   redundant keys.
-- [ ] **`<D-CR>` (Cmd+Return) tab-drop alias** _(new, 2026-05-31 re-audit)_ —
-  upstream binds both `<C-S-CR>` and the macOS `<D-CR>` to `VimwikiTabDropLink`;
-  nuwiki binds only `<C-S-CR>` (both clients). Niche (macOS GUI). _Fix:_
-  `lua/nuwiki/keymaps.lua`, `ftplugin/vimwiki.vim` alongside `<C-S-CR>`.
-- [ ] **`<Leader>w<Leader>m` missing from the Vim *global* map block** _(new)_ —
-  present buffer-locally in both clients, but `plugin/nuwiki.vim`'s global
-  `<Leader>w<Leader>*` family (usable from non-wiki buffers) binds `w`/`y`/`t`/`i`
-  but not `m` (tomorrow), which upstream binds globally. _Fix:_ `plugin/nuwiki.vim`.
+- [x] **`<D-CR>` (Cmd+Return) tab-drop alias** _(new, 2026-05-31 re-audit)_ —
+  added `<D-CR>` → `follow_link_drop` alongside `<C-S-CR>` in both clients
+  (`lua/nuwiki/keymaps.lua`, `ftplugin/vimwiki.vim`); docs updated. Covered by
+  `map[n].<D-CR>` in both harnesses.
+- [x] **`<Leader>w<Leader>m` missing from the Vim *global* map block** _(new)_ —
+  `plugin/nuwiki.vim`'s global family now binds `<Leader>w<Leader>m` (tomorrow)
+  and `<Leader>w<Leader>t` opens today in a new tab (was the same collision the
+  buffer-local maps had). Covered by `map[n].<Leader>w<Leader>m` in both harnesses.
 
 ---