refactor: restructure Bruno API collection for consistency

Standardize all Bruno API request files with consistent formatting and
structure to improve maintainability and readability.

Changes include:
- Consolidate URL parameters into main URL instead of separate definitions
- Standardize quote style (double quotes throughout)
- Add proper settings section with defaults (timeout, redirects, etc.)
- Improve YAML formatting with literal style for multi-line content
- Remove redundant fields (disabled: false)
- Clean up header and body structure
- Update sequence numbers for better organization
- Add scenarios folder structure for organized test groupings

Removes obsolete Search Invalid Library ID test case.

Environment configuration updated with new library_id for testing.

These changes improve the Bruno collection's maintainability and make
it easier to create new API requests following established patterns.

bruno/media-items/EPUB Download.yml

@@ -1,19 +1,23 @@
 info:
   name: Download Media Item
   type: http
-  seq: 1
+  seq: 4
+
 http:
   method: GET
-  url: '{{baseURL}}/api/media-items/{{bookUUID}}/download'
-  auth: none
-  body:
-    type: none
+  url: "{{base_url}}/api/media-items/{{media_item_id}}/download"
+
+settings:
+  encodeUrl: true
+  timeout: 0
+  followRedirects: true
+  maxRedirects: 5
 
 docs: |-
   ## Download Media Item
-  
+
     Download a media item file (EPUB, PDF, etc.) from Bookhoard server.
-  
+
     **Method:** GET
-  
+
     **Endpoint:** /api/media-items/{bookUUID