fix(follow-link): create missing page + wrap word on <CR>

Two missing pieces in the previous "follow creates page" fix:

1. **`wiki_root` never reached the server.** The Lua glue (and the
   Vim autoload glue) was sending the config under `settings` — that
   field is for `workspace/didChangeConfiguration` notifications, not
   for `initialize`. The server's `Config::from_init_params` reads
   `initialization_options`, so `wiki_root` arrived as `None`, the
   `Wiki` aggregate was empty, and `wiki_for_uri` returned `None` →
   `resolve_target_uri` bailed before reaching my synthesise path,
   leaving `<CR>` with "No Location Found".

   Both glues now send the same payload under both keys:
   - `lua/nuwiki/lsp.lua` → adds `init_options = init_options()`
     alongside the existing `settings = …`.
   - `autoload/nuwiki/lsp.vim` → adds `initialization_options` to
     the `lsp#register_server` call.

   The server keeps reading from `initializationOptions` at startup
   *and* honouring `didChangeConfiguration` later (Phase 11 plumbing).

2. **No-wiki fallback in the server.** Even with the glue fix above,
   users who launch nuwiki on an ad-hoc `.wiki` file outside any
   workspace folder would still get an empty `wikis` list. The
   `LinkKind::Wiki` arm now falls back to a new
   `synthesise_page_uri_next_to(source_uri, path)` which builds the
   future page next to the current file. `<CR>` on `[[NewPage]]`
   opens `./NewPage.wiki`, save creates it.

3. **`<CR>` on a plain word now wraps + follows.** Mirrors vimwiki's
   `:VimwikiFollowLink`: when the cursor isn't already inside
   `[[…]]`, the new `nuwiki.commands.follow_link_or_create` /
   `nuwiki#commands#follow_link_or_create` first wraps the word
   under cursor as `[[word]]`, places the cursor inside the link,
   then dispatches `vim.lsp.buf.definition()` /
   `:LspDefinition`. Both editor paths now bind `<CR>` /
   `<S-CR>` / `<C-CR>` / `<C-S-CR>` to this smart variant.

Verified end-to-end:
- `[[NewPage]]` with the rebuilt binary: definition returns
  `file:///tmp/wiki/NewPage.wiki` as a Location, so the editor
  opens an empty buffer for it.
- A bare `MyPage` word becomes `[[MyPage]]` in the buffer before
  the follow request fires.

Total 381 tests still pass; fmt + clippy clean.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

autoload/nuwiki/commands.vim

@@ -94,6 +94,69 @@ function! s:wiki_pick(notification) abort
         \ function('s:open_uri_from'))
 endfunction
 
+" ===== Smart <CR>: follow or wrap-then-follow =====
+
+function! s:cursor_inside_wikilink() abort
+  let l:line = getline('.')
+  let l:col = col('.')
+  let l:i = 1
+  let l:open = 0
+  while l:i < strlen(l:line)
+    if strpart(l:line, l:i - 1, 2) ==# '[['
+      let l:open = l:i
+      let l:i += 2
+    elseif strpart(l:line, l:i - 1, 2) ==# ']]'
+      let l:open = 0
+      let l:i += 2
+    else
+      let l:i += 1
+    endif
+    if l:i > l:col
+      break
+    endif
+  endwhile
+  return l:open > 0
+endfunction
+
+function! s:wrap_cword_as_wikilink() abort
+  let l:word = expand('<cword>')
+  if l:word ==# ''
+    return 0
+  endif
+  let l:line = getline('.')
+  let l:col = col('.')
+  " Find word boundaries around cursor (1-based).
+  let l:left = l:col
+  while l:left > 1 && strpart(l:line, l:left - 2, 1) =~# '[A-Za-z0-9_-]'
+    let l:left -= 1
+  endwhile
+  let l:right = l:col
+  while l:right <= strlen(l:line) && strpart(l:line, l:right - 1, 1) =~# '[A-Za-z0-9_-]'
+    let l:right += 1
+  endwhile
+  let l:word_real = strpart(l:line, l:left - 1, l:right - l:left)
+  if l:word_real ==# ''
+    return 0
+  endif
+  let l:new_line = strpart(l:line, 0, l:left - 1) . '[[' . l:word_real . ']]' . strpart(l:line, l:right - 1)
+  call setline('.', l:new_line)
+  call cursor(line('.'), l:left + 2)
+  return 1
+endfunction
+
+function! nuwiki#commands#follow_link_or_create() abort
+  if !s:cursor_inside_wikilink()
+    call s:wrap_cword_as_wikilink()
+  endif
+  if exists(':LspDefinition') == 2
+    LspDefinition
+  else
+    echohl WarningMsg
+    echom 'nuwiki: :LspDefinition unavailable; install vim-lsp'
+    echohl None
+  endif
+endfunction
+
 " Pure-VimL bullet-continuation for `o` / `O` — mirrors the Lua side
 " so re-pressing the key keeps the list marker (and checkbox if any).
 function! nuwiki#commands#open_below_with_bullet() abort

autoload/nuwiki/lsp.vim

@@ -36,6 +36,7 @@ function! nuwiki#lsp#start() abort
           \ 'name': 'nuwiki',
           \ 'cmd': {server_info -> [l:bin]},
           \ 'allowlist': ['vimwiki'],
+          \ 'initialization_options': s:settings(),
           \ 'config': { 'settings': { 'nuwiki': s:settings() } },
           \ })
     " vim-lsp auto-enables servers when 'g:lsp_auto_enable' is on