feat: Add "pub" syntax token

crates/plotnik-lib/src/parser/cst.rs

@@ -100,6 +100,9 @@ pub enum SyntaxKind {
     #[token("MISSING")]
     KwMissing,
 
+    #[token("pub")]
+    Pub,
+
     /// Identifier. Accepts dots/hyphens for tree-sitter compat; parser validates per context.
     /// Defined after keywords so they take precedence.
     #[regex(r"[a-zA-Z][a-zA-Z0-9_.\-]*")]

crates/plotnik-lib/src/parser/grammar.rs

@@ -21,21 +21,27 @@ impl Parser<'_> {
         let mut unnamed_def_spans: Vec<TextRange> = Vec::new();
 
         while !self.has_fatal_error() && (self.peek() != SyntaxKind::Error || !self.eof()) {
+            if self.peek() == SyntaxKind::Pub {
+                self.parse_def();
+                continue;
+            }
+
             // LL(2): Id followed by Equals → named definition (if PascalCase)
             if self.peek() == SyntaxKind::Id && self.peek_nth(1) == SyntaxKind::Equals {
                 self.parse_def();
-            } else {
-                let start = self.current_span().start();
-                self.start_node(SyntaxKind::Def);
-                let success = self.parse_expr_or_error();
-                if !success {
-                    self.synchronize_to_def_start();
-                }
-                self.finish_node();
-                if success {
-                    let end = self.last_non_trivia_end().unwrap_or(start);
-                    unnamed_def_spans.push(TextRange::new(start, end));
-                }
+                continue;
+            }
+
+            let start = self.current_span().start();
+            self.start_node(SyntaxKind::Def);
+            let success = self.parse_expr_or_error();
+            if !success {
+                self.synchronize_to_def_start();
+            }
+            self.finish_node();
+            if success {
+                let end = self.last_non_trivia_end().unwrap_or(start);
+                unnamed_def_spans.push(TextRange::new(start, end));
             }
         }
 
@@ -57,6 +63,9 @@ impl Parser<'_> {
     fn parse_def(&mut self) {
         self.start_node(SyntaxKind::Def);
 
+        self.eat(SyntaxKind::Pub);
+        self.peek();
+
         let span = self.current_span();
         let name = token_text(self.source, &self.tokens[self.pos]);
         self.bump();

crates/plotnik-lib/src/parser/tests/grammar/definitions_tests.rs

@@ -252,14 +252,15 @@ fn named_def_referencing_another() {
 #[test]
 fn named_def_with_quantifier() {
     let input = indoc! {r#"
-    Statements = (statement)+
+    pub Statements = (statement)+
     "#};
 
     let query = Query::try_from(input).unwrap();
     assert!(query.is_valid());
     insta::assert_snapshot!(query.dump_cst(), @r#"
     Root
       Def
+        Pub "pub"
         Id "Statements"
         Equals "="
         Quantifier