fix: Handle JavaScript class inheritance parsing differences from TypeScript

Addresses JavaScript `class extends` producing zero inheritance edges due to tree-sitter grammar differences. JavaScript uses `class_heritage → identifier` (bare) while TypeScript wraps with `extends_clause`. Updates extractInheritance to handle bare identifier/type_identifier children when parent is class_heritage.

docs/SEARCH_QUALITY_LOOP.md

@@ -459,6 +459,7 @@ test().catch(console.error);
 | Svelte template function calls invisible (e.g. `class={cn(...)}`) | SvelteExtractor only parsed `<script>` blocks, missing calls in template markup | `src/extraction/svelte-extractor.ts: extractTemplateCalls` scans `{expression}` blocks in template for call patterns |
 | Svelte `$state`/`$derived` rune calls creating noise | Runes are compiler builtins, not real function calls | `src/extraction/svelte-extractor.ts` filters `SVELTE_RUNES` set from unresolved references |
 | Object literal getters/setters extracted as standalone functions | `method_definition` inside `object` literals treated same as class methods | `src/extraction/tree-sitter.ts: extractMethod` skips `method_definition` nodes whose parent is `object`/`object_expression` |
+| JavaScript `class extends` produces zero inheritance edges | JS tree-sitter uses `class_heritage → identifier` (bare), not `class_heritage → extends_clause → identifier` like TypeScript | `src/extraction/tree-sitter.ts: extractInheritance` — handle bare `identifier`/`type_identifier` children when parent is `class_heritage` |
 
 ## After Fixing Issues
 

src/extraction/tree-sitter.ts

@@ -1688,6 +1688,22 @@ export class TreeSitterExtractor {
         }
       }
 
+      // JavaScript class_heritage has bare identifier without extends_clause wrapper
+      // e.g. `class Foo extends Bar {}` → class_heritage → identifier("Bar")
+      if (
+        (child.type === 'identifier' || child.type === 'type_identifier') &&
+        node.type === 'class_heritage'
+      ) {
+        const name = getNodeText(child, this.source);
+        this.unresolvedReferences.push({
+          fromNodeId: classId,
+          referenceName: name,
+          referenceKind: 'extends',
+          line: child.startPosition.row + 1,
+          column: child.startPosition.column,
+        });
+      }
+
       // Recurse into container nodes (e.g. field_declaration_list in Go structs,
       // class_heritage in TypeScript which wraps extends_clause/implements_clause)
       if (child.type === 'field_declaration_list' || child.type === 'class_heritage') {