feat(parity): P3 quick-wins — ShowVersion, gLH/gLL/gLR, Search/Align nargs

Closes four low-risk P3 parity items (gap doc updated):

- VimwikiShowVersion / NuwikiShowVersion: new global command (both clients)
  echoing g:nuwiki_version (0.1.0) + the host editor, via
  nuwiki#commands#show_version / commands.show_version.

- gLH / gLL / gLR: upstream's case-variant aliases of gLh/gLl/gLr (dedent /
  indent whole item, renumber all lists) added in both clients.

- VimwikiSearch / VWS: -nargs=1 -> -nargs=* (Vim + Neovim), so a multi-word
  search no longer raises E488 and an empty invocation reuses the last search
  pattern. (The lvimgrep-vs-vimwiki-engine difference stays open.)

- VimwikiTableAlignQ / AlignW / NuwikiTableAlign: bare -> -nargs=?, so
  `:VimwikiTableAlignQ 2` no longer raises E488 (optional column arg is
  accepted-and-ignored; the gqq-align vs gww-align-without-resize split
  stays open).

Docs (doc/nuwiki.txt + README) updated for the command and the aliases.
Tests: surface.{Vimwiki,Nuwiki}ShowVersion, map[n].gL{H,L,R} (both
harnesses), cmd.search_and_tablealign_nargs (vim). Neovim 291, Vim
282/18/21 pass.

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

development/vimwiki-gap.md

@@ -173,12 +173,20 @@ fix site.
 
 ### Commands
 - [ ] `VimwikiVar` — config-var get/set introspection. _Fix:_ `plugin/nuwiki.vim`.
-- [ ] `VimwikiShowVersion` — print version (trivial). _Fix:_ `plugin/nuwiki.vim`.
+- [x] **`VimwikiShowVersion`** _(fixed 2026-06-03)_ — added global
+  `VimwikiShowVersion`/`NuwikiShowVersion` (both clients) echoing
+  `g:nuwiki_version` (`0.1.0`) + the host editor, via
+  `nuwiki#commands#show_version` / `commands.show_version`. Covered by
+  `surface.{Vimwiki,Nuwiki}ShowVersion` in both keymap harnesses.
 - [ ] `VimwikiReturn` — no Ex-command (mapping-driven only). _Fix:_ `ftplugin/vimwiki.vim`.
 - [ ] `VimwikiTableAlignQ` vs `AlignW` collapsed to one `table_align` — `gqq`
-  (align) vs `gww` (align w/o resize) distinction lost. _(Re-audit 2026-05-31:
-  also note the attr differs — both are defined bare in all four contexts vs
-  upstream's `-nargs=?`, so `:VimwikiTableAlignQ 2` raises E488.)_
+  (align) vs `gww` (align w/o resize) distinction still lost (the remaining
+  open part). _(Re-audit 2026-05-31: also the attr differed — bare vs upstream's
+  `-nargs=?`, so `:VimwikiTableAlignQ 2` raised E488.)_ _Attr part fixed
+  2026-06-03:_ `VimwikiTableAlignQ`/`AlignW` + `NuwikiTableAlign` are now
+  `-nargs=?` in all contexts (the optional column arg is accepted-and-ignored
+  pending the align-vs-resize split), so the E488 is gone. Covered by
+  `cmd.search_and_tablealign_nargs` (`test-keymaps-vim.vim`).
 - [x] `VimwikiTable` was `-nargs=1` vs upstream `-nargs=*` (couldn't pass
   cols+rows). _Fix:_ all four defs (Vim+Neovim × Vimwiki+Nuwiki) are now
   `-nargs=*` and forward `<f-args>` to `table_insert` (which already parsed
@@ -224,9 +232,13 @@ fix site.
   `{ all: true }`; the server (`tags_rebuild`) re-indexes **every** configured
   wiki (via `wikis_snapshot()`) instead of just the current one. `-bang` added to
   all four command defs.
-- [ ] `:VimwikiSearch` / `VWS` uses `lvimgrep`, not vimwiki's search engine.
-  _(Re-audit 2026-05-31: also `-nargs=1` in all four contexts vs upstream
-  `-nargs=*`.)_
+- [ ] `:VimwikiSearch` / `VWS` uses `lvimgrep`, not vimwiki's search engine
+  (the remaining open part — a deliberate, simpler implementation). _(Re-audit
+  2026-05-31: also `-nargs=1` vs upstream `-nargs=*`.)_ _Attr part fixed
+  2026-06-03:_ both are now `-nargs=*` (Vim + Neovim), so a multi-word
+  `:VimwikiSearch foo bar` no longer raises E488 and an empty `:VimwikiSearch`
+  reuses the last search pattern (`lvimgrep //`). Covered by
+  `cmd.search_and_tablealign_nargs` (`test-keymaps-vim.vim`).
 - [x] **`VimwikiChangeSymbolTo` / `VimwikiListChangeSymbolI` lack `-range`**
   _(new, 2026-05-31 re-audit; fixed same day)_ — upstream both carry
   `-range -nargs=1`; nuwiki had `-nargs=1` only, so a visual-range invocation
@@ -476,11 +488,12 @@ fix site.
 ### Mappings
 - [ ] Visual `<CR>` normalize-link (visual `+` covers the same intent).
 - [ ] Insert `<S-CR>` multiline list item.
-- [ ] `gLH` / `gLL` / `gLR` — upstream binds these as case-variant **aliases**
-  of `gLh` / `gLl` / `gLr` (same actions: dedent / indent whole item, renumber
-  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.
+- [x] **`gLH` / `gLL` / `gLR`** _(fixed 2026-06-03)_ — upstream binds these as
+  case-variant **aliases** of `gLh` / `gLl` / `gLr` (dedent / indent whole item,
+  renumber all lists; upstream `ftplugin/vimwiki.vim:553,555,561`). nuwiki had
+  only the lowercase forms. _Fix:_ added the uppercase-suffix aliases (same
+  actions) in both clients (`lua/nuwiki/keymaps.lua`, `ftplugin/vimwiki.vim`).
+  Covered by `map[n].gL{H,L,R}` in both harnesses.
 - [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