chore: Clean up and reorganize Bruno collection after rebuild

- Remove duplicate Get Admin Dashboard.bru (same as /admin route)
- Reorder sequence numbers for logical grouping
- Add missing body: none to GET requests
- Standardize folder path examples to /app/uploads
- Fix file formatting and add missing newlines

bruno/admin/Get Ebook Folders.bru

@@ -1,7 +1,7 @@
 meta {
   name: Get Ebook Folders
   type: http
-  seq: 9
+  seq: 2
 }
 
 get {
@@ -43,4 +43,4 @@ docs {
   - Returns all folders configured for the user
   - Useful for folder management interfaces
   - Empty array returned if no folders configured
-}
+}