feat(commands): ChangeSymbolTo -range, GenerateLinks path filter, NuwikiGenerateTags

Closes the three new command gaps from the 2026-05-31 re-audit (all real,
client-side, both clients × Vimwiki/Nuwiki):

- VimwikiChangeSymbolTo / ListChangeSymbolI / NuwikiChangeSymbol are now
  -range -nargs=1 via a new list_change_symbol_range(symbol,l1,l2) helper that
  loops over_range; was -nargs=1 only → E481 on a visual selection.
  ChangeSymbolInListTo/InList stay range-less.
  Bonus: the Neovim VimwikiChangeSymbolInListTo + NuwikiChangeSymbolInList defs
  passed whole_list=false, changing only the current item — corrected to true.

- VimwikiGenerateLinks / NuwikiGenerateLinks are now -nargs=?; with an arg the
  client dispatches the existing server command nuwiki.links.generateForPath
  ({path}) for real subtree-scoped link generation, else nuwiki.links.generate.
  Was bare → E488 on an arg.

- Added NuwikiGenerateTags (Vim + Neovim) mirroring VimwikiGenerateTags, with
  -nargs=? -complete=…tags — closes the :Vimwiki*↔:Nuwiki* alias asymmetry.

Tests: cmd.ChangeSymbolTo_range_sets_marker, cmd.GenerateLinks_accepts_optional_path,
cmd.NuwikiGenerateTags_exists (test-keymaps.lua, 283 pass) +
cmd.VimwikiChangeSymbolTo_accepts_range, cmd.VimwikiGenerateLinks_accepts_path,
cmd.NuwikiGenerateTags_exists (test-keymaps-vim.vim, 272/18/21). fmt clean.

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

development/vimwiki-gap.md

@@ -227,23 +227,33 @@ fix site.
 - [ ] `:VimwikiSearch` / `VWS` uses `lvimgrep`, not vimwiki's search engine.
   _(Re-audit 2026-05-31: also `-nargs=1` in all four contexts vs upstream
   `-nargs=*`.)_
-- [ ] **`VimwikiChangeSymbolTo` / `VimwikiListChangeSymbolI` lack `-range`**
-  _(new, 2026-05-31 re-audit)_ — upstream both carry `-range -nargs=1`; nuwiki
-  defines them `-nargs=1` only (both branches), so `:'<,'>VimwikiChangeSymbolTo X`
-  over a visual selection raises `E481: No range allowed`. (Internally
-  consistent across nuwiki's four contexts; purely an upstream-parity gap.)
-  `ChangeSymbolInListTo` is correctly range-less. _Fix:_ add `-range` + a
-  `*_range` loop, mirroring the `ToggleListItem`/`IncrementListItem` range work.
-- [ ] **`VimwikiGenerateLinks` lacks `-nargs=?`** _(new, 2026-05-31 re-audit)_ —
-  upstream takes an optional rel-path arg (`-nargs=?`); nuwiki defines it bare in
-  all four contexts, so `:VimwikiGenerateLinks foo` raises `E488`. Low impact
-  (the arg is rarely used). _Fix:_ `ftplugin/vimwiki.vim` + thread an optional
-  path into `links_generate`.
-- [ ] **`NuwikiGenerateTags` missing** _(new, 2026-05-31 re-audit)_ — the
-  `:Nuwiki*` surface lacks a `GenerateTags` alias although `:VimwikiGenerateTags`
-  exists (both branches) and `NuwikiGenerateTagLinks` (same handler) is present.
-  Internal `:Vimwiki*`↔`:Nuwiki*` asymmetry; trivial. _Fix:_ add the two
-  `NuwikiGenerateTags` defs (Vim + Neovim) mirroring `VimwikiGenerateTags`.
+- [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
+  raised `E481`. _Fix:_ all four defs (Vim+Neovim × the `Vimwiki*`/`Nuwiki*`
+  current-item forms — `VimwikiChangeSymbolTo`/`ListChangeSymbolI` and
+  `NuwikiChangeSymbol`) are now `-range -nargs=1` passing `<line1>,<line2>,
+  <q-args>` to a new `list_change_symbol_range(symbol, l1, l2)` helper that
+  loops `over_range` (both clients). `ChangeSymbolInListTo`/`InList` stay
+  range-less. **Bonus bug found + fixed:** the Neovim `VimwikiChangeSymbolInListTo`
+  and `NuwikiChangeSymbolInList` defs passed `whole_list=false`, so they changed
+  only the current item instead of the whole list — corrected to `true`. Covered
+  by `cmd.ChangeSymbolTo_range_sets_marker` (`test-keymaps.lua`) +
+  `cmd.VimwikiChangeSymbolTo_accepts_range` (`test-keymaps-vim.vim`).
+- [x] **`VimwikiGenerateLinks` lacks `-nargs=?`** _(new, 2026-05-31 re-audit;
+  fixed same day)_ — upstream takes an optional rel-path arg; nuwiki was bare,
+  so `:VimwikiGenerateLinks foo` raised `E488`. _Fix:_ all four defs are now
+  `-nargs=?`; `links_generate([path])` (both clients) dispatches the existing
+  server command `nuwiki.links.generateForPath` (with `{path}`) when an arg is
+  given, else `nuwiki.links.generate` — a **real** path filter, not
+  accepted-and-ignored (the server's `links_generate_for_path` already
+  implements subtree scoping). Covered by
+  `cmd.GenerateLinks_accepts_optional_path` (`test-keymaps.lua`) +
+  `cmd.VimwikiGenerateLinks_accepts_path` (`test-keymaps-vim.vim`).
+- [x] **`NuwikiGenerateTags` missing** _(new, 2026-05-31 re-audit; fixed same
+  day)_ — added `NuwikiGenerateTags` (Vim + Neovim) mirroring
+  `VimwikiGenerateTags` → `tags_generate_links`, with `-nargs=?` +
+  `-complete=…tags`. Covered by `cmd.NuwikiGenerateTags_exists` (both harnesses).
 - [ ] `VimwikiIndex` family is buffer-local in nuwiki (upstream defines globally
   in `plugin/`); only `:…UISelect` is a global entry point.
 - [x] **`VimwikiColorize` / `NuwikiColorize` drop their argument in the Neovim