Rename grammar "definition" to "relation"

crates/frontend/src/ast.rs

@@ -50,7 +50,7 @@ pub fn items<'db>(db: &'db dyn Database, file: workspace::File) -> Vec<ItemMeta<
             // otherwise, convert the symbol directly into the item kind
             "type_alias" => ItemKind::TypeAlias,
             "import" => ItemKind::Import,
-            "definition" => ItemKind::Relation, // TODO: rename grammar node
+            "relation" => ItemKind::Relation,
             "rule" => ItemKind::Rule,
             "assumption" => ItemKind::Assumption,
 
@@ -115,7 +115,7 @@ pub enum Item<'db> {
 /// Parses [Relation] from an [AstNode].
 #[salsa::tracked]
 pub fn relation<'db>(db: &'db dyn Database, ast: AstNode) -> Relation<'db> {
-    let name = ast.expect_field(db, "relation").with_contents(db);
+    let name = ast.expect_field(db, "name").with_contents(db);
     let is_decision = ast.get_field(db, "decision").is_some();
     let ty = ty(db, ast.expect_field(db, "type"));
     Relation::new(db, name, is_decision, ty)