fix(build): resolve patter relative to srcDir instead of root in createContentLoader (#3638)

Co-authored-by: Divyansh Singh <40380293+brc-dd@users.noreply.github.com>

src/node/contentLoader.ts

@@ -75,7 +75,7 @@ export interface ContentData {
  */
 export function createContentLoader<T = ContentData[]>(
   /**
-   * files to glob / watch - relative to <project root>
+   * files to glob / watch - relative to srcDir
    */
   pattern: string | string[],
   {
@@ -98,7 +98,7 @@ export function createContentLoader<T = ContentData[]>(
   }
 
   if (typeof pattern === 'string') pattern = [pattern]
-  pattern = pattern.map((p) => normalizePath(path.join(config.root, p)))
+  pattern = pattern.map((p) => normalizePath(path.join(config.srcDir, p)))
 
   let md: MarkdownRenderer