feat(xatu): add manual inherit lint

src/xatu/rules.rs

@@ -1,7 +1,9 @@
 use crate::FileId;
 use crate::ast;
+use crate::rules::manual_inherit::ManualInherit;
 use crate::rules::unquoted_uri::UnquotedUri;
 
+pub mod manual_inherit;
 pub mod unquoted_uri;
 
 #[derive(Debug)]
@@ -27,7 +29,6 @@ impl std::fmt::Display for Diagnostic {
     }
 }
 
-#[expect(dead_code, reason = "retained for planned node rules")]
 pub trait NodeRule {
     type Node;
 
@@ -47,7 +48,11 @@ pub trait TokenRule {
 }
 
 pub fn run_rules(file: &ast::ParsedFile) -> Vec<Diagnostic> {
-    let node_diagnostics = file.nodes.iter().flat_map(|_| std::iter::empty());
+    let node_diagnostics = file
+        .nodes
+        .iter()
+        .flat_map(|node| [run_node_rule::<ManualInherit>(node)])
+        .flatten();
     let token_diagnostics = file
         .tokens
         .iter()
@@ -63,7 +68,6 @@ pub fn run_rules(file: &ast::ParsedFile) -> Vec<Diagnostic> {
         .collect()
 }
 
-#[expect(dead_code, reason = "retained for planned node rules")]
 fn run_node_rule<R>(node: &ast::Node) -> Option<Finding>
 where
     R: NodeRule,