fix: handle both forward and backward slashes in getCategoryDisplayName

This aligns with the pattern used in isApiReferencePath and fixes incorrect category detection on Windows systems where paths normalized to forward slashes would fail to split correctly.

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Co-Authored-By: Claude <[email protected]>

Author: derrekcoleman

lib/files.ts

@@ -21,7 +21,7 @@ export const DOCS_CATEGORIES = {
 export type CategoryType = keyof typeof DOCS_CATEGORIES;
 
 export function getCategoryDisplayName(filePath: string): string {
-  const pathParts = filePath.split(path.sep);
+  const pathParts = filePath.split(/[/\\]/);
   const mainCategory = pathParts[0];
   if (mainCategory && mainCategory in DOCS_CATEGORIES)
     return DOCS_CATEGORIES[mainCategory as CategoryType];