feat(lsp): wire diary/auto_toc/links_space_char/list_margin; drop client-side keys

Consume several per-wiki config keys that the server deserialized but
ignored, and remove keys whose effect is purely client-side:

- diagnostics: re-publish open-doc diagnostics on
  didChangeConfiguration so a link_severity change takes effect
  immediately; fix the single-key unwrap in apply_change so a minimal
  `{ diagnostic: {...} }` payload isn't mistaken for a namespace wrapper.
- auto_toc: rebuild an existing TOC section on save (new
  ops::toc_rebuild_edit, no-op when the page has no TOC).
- diary index: honour diary_header, diary_sort and diary_caption_level
  when rendering the diary index body.
- links_space_char: apply on rename so spaces in the link target and
  the on-disk path become the configured glyph (default " " = verbatim).
- list_margin: thread the per-wiki value into render_page_html.
- remove nested_syntaxes, maxhi and diary_start_week_day from the server
  config: nested-syntax and heading highlighting are client-side, and
  the weekly diary is ISO-week based so a custom week start has no clean
  server-side meaning.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

crates/nuwiki-lsp/tests/commands_coverage.rs

@@ -21,7 +21,7 @@ use nuwiki_lsp::commands::{export_ops, ops, COMMANDS};
 use nuwiki_lsp::config::WikiConfig;
 use nuwiki_lsp::index::WorkspaceIndex;
 use nuwiki_lsp::nav::find_inline_at;
-use nuwiki_lsp::rename::{build_new_uri, rewrite_wikilink_target};
+use nuwiki_lsp::rename::{apply_links_space_char, build_new_uri, rewrite_wikilink_target};
 use nuwiki_lsp::wiki::{build_wikis, resolve_uri_to_wiki};
 use nuwiki_lsp::{diary, export};
 use tower_lsp::lsp_types::Url;
@@ -177,6 +177,30 @@ fn nuwiki_rename_file_builds_uri_and_rewrites_links() {
     );
 }
 
+// links_space_char rewrites spaces in the link target / on-disk path while
+// the default of a single space keeps the name verbatim.
+#[test]
+fn links_space_char_replaces_spaces_in_target_path() {
+    // Default " " — identity, spaces preserved.
+    assert_eq!(apply_links_space_char("My Page", " "), "My Page");
+    // Custom char — spaces become the configured glyph.
+    assert_eq!(apply_links_space_char("My Page", "_"), "My_Page");
+    // Subdir separators are untouched; only spaces within segments change.
+    assert_eq!(
+        apply_links_space_char("sub dir/My Page", "_"),
+        "sub_dir/My_Page"
+    );
+
+    // The transformed name flows into both the new URI and the rewritten link.
+    let renamed = apply_links_space_char("New Page", "-");
+    let new_uri = build_new_uri(&PathBuf::from("/wiki"), &renamed, ".wiki").unwrap();
+    assert!(new_uri.as_str().ends_with("/wiki/New-Page.wiki"));
+    assert_eq!(
+        rewrite_wikilink_target("[[Old Name|caption]]", &renamed),
+        Some("[[New-Page|caption]]".to_string())
+    );
+}
+
 // :NuwikiDeleteFile — delete the current page and its on-disk file.
 #[test]
 fn nuwiki_delete_file_emits_delete_workspace_edit() {
@@ -238,7 +262,7 @@ fn nuwiki_diary_index_resolves_index_uri() {
 fn nuwiki_diary_generate_links_builds_grouped_body() {
     let idx = diary_index("/wiki", &["2026-05-10", "2026-05-12", "2026-04-30"]);
     let entries = diary::list_entries(&idx);
-    let body = diary::build_index_body(&entries, "diary", "Diary");
+    let body = diary::build_index_body(&entries, "diary", "Diary", diary::DiarySort::Desc, 1);
     assert!(body.starts_with("= Diary ="));
     assert!(body.contains("2026-05-12"));
     assert!(body.contains("2026-05-10"));
@@ -407,6 +431,7 @@ fn nuwiki_2html_renders_page() {
         DiaryDate::from_ymd(2026, 5, 12).unwrap(),
         &cfg.html,
         Some(".wiki"),
+        -1,
         HashMap::new(),
     )
     .unwrap();
@@ -428,6 +453,7 @@ fn nuwiki_2html_browse_shares_render_and_is_advertised() {
         DiaryDate::today_utc(),
         &cfg.html,
         Some(".wiki"),
+        -1,
         HashMap::new(),
     )
     .unwrap();