feat(config): P3 config batch — group 1 (clean config + plumbing)

Config plumbing for the whole config batch (HtmlConfig + WikiConfig fields,
RawWiki deserialization, From/defaults) plus these behaviors:

- rss_name / rss_max_items: HtmlConfig fields (wired into write_rss in the RSS
  group).
- toc_link_format: build_toc_text emits [[#anchor]] (no description) for 1,
  [[#anchor|title]] for 0.
- generated_links_caption: build_links_text emits [[page|FirstHeading]] from a
  page->heading map (ops::page_captions) when enabled.
- table_reduce_last_col: column_widths clamps the last column to width 1 when
  set; threaded through table_align_edit/table_move_column_edit + commands.
- color_dic now ships a populated default palette (red/green/blue/...).
- commentstring aligned to upstream's no-space `%%%s`.
- auto_chdir (default off): :lcd into the owning wiki root on buffer enter;
  both clients (ftplugin.lua setup_auto_chdir + Vim NuwikiAutoChdir augroup),
  with config.wiki_root_for / nuwiki#commands#wiki_root_for resolvers.

Also seeded HtmlConfig fields for later groups (valid_html_tags,
list/text_ignore_newline, emoji_enable, user_htmls, color_tag_template) and
WikiConfig (create_link, dir_link, bullet_types, cycle_bullets).

Tests: toc_link_format, generated_links_caption, table_reduce_last_col,
config defaults + JSON round-trip for every new key. Full rust suite +
both keymap harnesses green.

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

crates/nuwiki-lsp/tests/index_and_config.rs

@@ -295,6 +295,63 @@ fn defaults_carry_vimwiki_per_wiki_keys() {
     // HTML section numbering is off by default (vimwiki's `0`).
     assert_eq!(cfg.html.html_header_numbering, 0);
     assert_eq!(cfg.html.html_header_numbering_sym, "");
+    // New config defaults match upstream.
+    assert!(cfg.create_link);
+    assert_eq!(cfg.dir_link, "");
+    assert_eq!(cfg.bullet_types, vec!["-", "*", "#"]);
+    assert!(!cfg.cycle_bullets);
+    assert!(!cfg.generated_links_caption);
+    assert_eq!(cfg.toc_link_format, 0);
+    assert!(!cfg.table_reduce_last_col);
+    assert_eq!(cfg.html.rss_name, "rss.xml");
+    assert_eq!(cfg.html.rss_max_items, 10);
+    assert!(cfg.html.list_ignore_newline);
+    assert!(cfg.html.text_ignore_newline);
+    assert!(cfg.html.emoji_enable);
+    assert!(cfg.html.user_htmls.is_empty());
+    assert!(cfg.html.valid_html_tags.contains(&"sub".to_string()));
+    // color_dic ships a populated palette (vimwiki seeds one).
+    assert!(cfg.html.color_dic.contains_key("red"));
+}
+
+#[test]
+fn raw_wiki_parses_config_batch_keys() {
+    let cfg = config_from_json(serde_json::json!({
+        "wikis": [{
+            "root": "/tmp/w",
+            "create_link": false,
+            "dir_link": "index",
+            "bullet_types": ["+", "-"],
+            "cycle_bullets": true,
+            "generated_links_caption": 1,
+            "toc_link_format": 1,
+            "table_reduce_last_col": true,
+            "rss_name": "feed.xml",
+            "rss_max_items": 5,
+            "valid_html_tags": "b,mark",
+            "list_ignore_newline": 0,
+            "text_ignore_newline": false,
+            "emoji_enable": 0,
+            "user_htmls": ["404.html"],
+            "color_tag_template": "<u>__CONTENT__</u>",
+        }],
+    }));
+    let w = &cfg.wikis[0];
+    assert!(!w.create_link);
+    assert_eq!(w.dir_link, "index");
+    assert_eq!(w.bullet_types, vec!["+", "-"]);
+    assert!(w.cycle_bullets);
+    assert!(w.generated_links_caption);
+    assert_eq!(w.toc_link_format, 1);
+    assert!(w.table_reduce_last_col);
+    assert_eq!(w.html.rss_name, "feed.xml");
+    assert_eq!(w.html.rss_max_items, 5);
+    assert_eq!(w.html.valid_html_tags, vec!["b", "mark"]);
+    assert!(!w.html.list_ignore_newline);
+    assert!(!w.html.text_ignore_newline);
+    assert!(!w.html.emoji_enable);
+    assert_eq!(w.html.user_htmls, vec!["404.html"]);
+    assert_eq!(w.html.color_tag_template, "<u>__CONTENT__</u>");
 }
 
 #[test]