feat(config): make listsym_rejected configurable (P2)

The rejected/cancelled checkbox glyph was a hardcoded `const REJECTED = '-'`.
ListSyms now carries a `rejected` field (new_with_rejected); a per-wiki
`listsym_rejected` key (default `-`) is added to WikiConfig, and
WikiConfig::list_syms() builds the palette with it. Routed the three
config-driven ListSyms construction sites (parse path in lib.rs + the
toggle/cycle commands) through list_syms(), so a custom rejected glyph both
lexes and round-trips.

Tests: listsyms::custom_rejected_glyph_is_honoured + config round-trip.
README/doc/lua config comment updated. fmt clean; 0 Rust test failures.

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

crates/nuwiki-lsp/src/commands.rs

@@ -250,7 +250,7 @@ fn list_checkbox(
     let wiki = backend.wiki_for_uri(&p.uri);
     let syms = wiki
         .as_ref()
-        .map(|w| nuwiki_core::listsyms::ListSyms::new(&w.config.listsyms))
+        .map(|w| w.config.list_syms())
         .unwrap_or_default();
     let propagate = wiki.map(|w| w.config.listsyms_propagate).unwrap_or(true);
     Ok(ops::checkbox_edit(
@@ -1184,10 +1184,8 @@ fn export_all(backend: &Backend, args: Vec<Value>, force: bool) -> Result<Option
                 let Ok(text) = std::fs::read_to_string(path) else {
                     continue;
                 };
-                let ast = nuwiki_core::syntax::vimwiki::VimwikiSyntax::new().parse_with_listsyms(
-                    &text,
-                    &nuwiki_core::listsyms::ListSyms::new(&cfg.listsyms),
-                );
+                let ast = nuwiki_core::syntax::vimwiki::VimwikiSyntax::new()
+                    .parse_with_listsyms(&text, &cfg.list_syms());
                 (text, ast)
             }
         };

crates/nuwiki-lsp/src/config.rs

@@ -61,6 +61,9 @@ pub struct WikiConfig {
     /// glyphs and the toggle/cycle commands walk them. Any length ≥ 2 is
     /// honoured. Default: `" .oOX"`.
     pub listsyms: String,
+    /// Vimwiki's `g:vimwiki_listsym_rejected` — the glyph for a cancelled
+    /// checkbox (`[-]` by default). First character is used.
+    pub listsym_rejected: String,
     /// When toggling a parent list item, also cascade to descendants.
     pub listsyms_propagate: bool,
     /// `-1` keeps tight lists; positive integers indent list items by
@@ -188,6 +191,7 @@ impl WikiConfig {
             diary_sort: d.diary_sort,
             diary_header: d.diary_header,
             listsyms: d.listsyms,
+            listsym_rejected: d.listsym_rejected,
             listsyms_propagate: d.listsyms_propagate,
             list_margin: d.list_margin,
             links_space_char: d.links_space_char,
@@ -217,6 +221,7 @@ impl WikiConfig {
             diary_sort: d.diary_sort,
             diary_header: d.diary_header,
             listsyms: d.listsyms,
+            listsym_rejected: d.listsym_rejected,
             listsyms_propagate: d.listsyms_propagate,
             list_margin: d.list_margin,
             links_space_char: d.links_space_char,
@@ -258,6 +263,13 @@ impl WikiConfig {
         nuwiki_core::date::DiaryFrequency::parse(&self.diary_frequency)
     }
 
+    /// The checkbox palette for this wiki — the `listsyms` progression plus
+    /// the configured `listsym_rejected` glyph (default `-`).
+    pub fn list_syms(&self) -> nuwiki_core::listsyms::ListSyms {
+        let rejected = self.listsym_rejected.chars().next().unwrap_or('-');
+        nuwiki_core::listsyms::ListSyms::new_with_rejected(&self.listsyms, rejected)
+    }
+
     /// The diary navigation policy (frequency + weekly naming/week-start),
     /// used by the diary commands to compute today / next / prev.
     pub fn diary_calendar(&self) -> nuwiki_core::date::DiaryCalendar {
@@ -306,6 +318,10 @@ fn default_listsyms() -> String {
     " .oOX".to_string()
 }
 
+fn default_listsym_rejected() -> String {
+    "-".to_string()
+}
+
 fn default_links_space_char() -> String {
     " ".to_string()
 }
@@ -327,6 +343,7 @@ fn wiki_defaults() -> WikiDefaults {
         diary_sort: default_diary_sort(),
         diary_header: default_diary_header(),
         listsyms: default_listsyms(),
+        listsym_rejected: default_listsym_rejected(),
         listsyms_propagate: true,
         list_margin: -1,
         links_space_char: default_links_space_char(),
@@ -345,6 +362,7 @@ struct WikiDefaults {
     diary_sort: String,
     diary_header: String,
     listsyms: String,
+    listsym_rejected: String,
     listsyms_propagate: bool,
     list_margin: i32,
     links_space_char: String,
@@ -565,6 +583,8 @@ struct RawWiki {
     diary_header: Option<String>,
     #[serde(default)]
     listsyms: Option<String>,
+    #[serde(default)]
+    listsym_rejected: Option<String>,
     #[serde(default, deserialize_with = "opt_bool_or_int::deserialize")]
     listsyms_propagate: Option<bool>,
     #[serde(default)]
@@ -629,6 +649,7 @@ impl From<RawWiki> for WikiConfig {
             diary_sort: r.diary_sort.unwrap_or(d.diary_sort),
             diary_header: r.diary_header.unwrap_or(d.diary_header),
             listsyms: r.listsyms.unwrap_or(d.listsyms),
+            listsym_rejected: r.listsym_rejected.unwrap_or(d.listsym_rejected),
             listsyms_propagate: r.listsyms_propagate.unwrap_or(d.listsyms_propagate),
             list_margin: r.list_margin.unwrap_or(d.list_margin),
             links_space_char: r.links_space_char.unwrap_or(d.links_space_char),

crates/nuwiki-lsp/src/lib.rs

@@ -193,7 +193,7 @@ impl Backend {
     fn parse_for_uri(&self, uri: &Url, text: &str) -> nuwiki_core::ast::DocumentNode {
         let syms = self
             .wiki_for_uri(uri)
-            .map(|w| nuwiki_core::listsyms::ListSyms::new(&w.config.listsyms))
+            .map(|w| w.config.list_syms())
             .unwrap_or_default();
         nuwiki_core::syntax::vimwiki::VimwikiSyntax::new().parse_with_listsyms(text, &syms)
     }