fix(keymaps): correct Neovim global diary tab/tomorrow maps (map_prefix audit)

A map_prefix parity audit against upstream vimwiki found the Neovim global
entry-point block in lua/nuwiki/init.lua carried the same collision the Vim
global + buffer-local maps were already fixed for: <prefix><Leader>t was
bound to tomorrow and <prefix><Leader>m (tomorrow) was missing entirely.

Now <prefix><Leader>t opens today in a new tab and <prefix><Leader>m is
tomorrow — consistent with plugin/nuwiki.vim, the buffer-local maps, and
upstream (VimwikiTabMakeDiaryNote / VimwikiMakeTomorrowDiaryNote).

Adds global_maps.diary_tab_and_tomorrow_targets to test-keymaps.lua (queries
in a scratch buffer so buffer-local maps don't shadow the globals). Logs the
fix plus a new "RSS feed structure fidelity" gap (the audit confirmed the
custom_wiki2html arg contract and base_url scope are faithful; only the RSS
document shape diverges) in development/vimwiki-gap.md.

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

development/vimwiki-gap.md

@@ -267,6 +267,16 @@ fix site.
 - [ ] `commentstring` (`'%%%s'`) — comment toggling/text-objects.
 - [ ] `color_tag_template` — `color_dic` present; template regex missing.
 - [ ] `rss_max_items` / `rss_name` — `:Rss` output hardcoded. _Fix:_ `HtmlConfig`.
+- [ ] **RSS feed structure fidelity** _(new, 2026-05-31 base_url audit)_ —
+  nuwiki's `write_rss` is intentionally minimal (title/link/guid). Upstream
+  emits more: channel `<link>` points at the diary index page
+  (`base_url + diary_rel_path + diary_index + .html`, nuwiki uses bare
+  `base_url`); per-item `<guid isPermaLink="false">` holds the bare date
+  basename (nuwiki uses the full URL, no attribute); plus `<atom:link rel=
+  "self">`, channel/item `<pubDate>` (from mtime), and a `<![CDATA[…]]>`
+  rendered-HTML body per item. `base_url`'s *scope* is faithful (RSS-only,
+  not inter-page links) and the `custom_wiki2html` arg contract is an exact
+  match — only the feed document shape diverges.
 - [ ] `emoji_enable` — emoji substitution.
 - [ ] `html_header_numbering` (+`_sym`) — numbered HTML headers.
 - [ ] `valid_html_tags` — allowed inline HTML tags in export.
@@ -289,6 +299,13 @@ fix site.
   `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.
+- [x] **`<Leader>w<Leader>m` missing from the Neovim *global* map block**
+  _(new, 2026-05-31 map_prefix audit)_ — the same collision survived in
+  `lua/nuwiki/init.lua`'s `_setup_global_mappings`: `<prefix><Leader>t` was
+  bound to tomorrow and `<prefix><Leader>m` (tomorrow) was absent entirely.
+  Fixed so `<prefix><Leader>t` opens today in a new tab and `<prefix><Leader>m`
+  is tomorrow — now consistent with the Vim global side + upstream. Covered by
+  `global_maps.diary_tab_and_tomorrow_targets` (`test-keymaps.lua`).
 
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