Revert "fix: filter depth >= 3 from tree display"

This reverts commit 845c91f676.

src/components/ApiDocViewer.tsx

@@ -72,7 +72,13 @@ export const ApiDocViewer = ({ onDocsPathChange, showAddModal, onCloseAddModal }
       setExternalDocs(docs)
       
       const fileList = docs
-        .filter(doc => doc.relativePath.split('/').length < 3)
+        .filter(doc => {
+          const parts = doc.relativePath.split('/')
+          if (parts.length < 2) return true
+          const filename = parts[parts.length - 1].replace(/\.md$/, '')
+          const parentFolder = parts[parts.length - 2]
+          return filename !== parentFolder
+        })
         .map(d => d.relativePath)
       const tree = buildFileTree(fileList, '/')
       setFileTree(tree)