test: improve Bruno API collection formatting and automation

This commit improves the Bruno API collection with better formatting,
updated test environment variables, and automation scripts for easier
API testing workflow.

## Environment Updates

- bruno/environments/Bookhoard.yml: Updated test IDs for library_id
  and job_id to reflect latest test database state

## Formatting Improvements

Updated all Bruno collection files with consistent formatting:
- bruno/highlights/Create Media Highlight.yml
- bruno/highlights/Update Media Highlight.yml
- bruno/library/Add Library Folder.yml
- bruno/library/Create Library.yml
- bruno/library/Delete Library.yml
- bruno/library/Set Library Visibility.yml
- bruno/media-items/Create Media Item.yml
- bruno/media-items/Create Media Rating.yml
- bruno/media-items/Update Media Item.yml
- bruno/media-items/Update Media Rating.yml
- bruno/media-items/search/Combined Search and Filters.yml
- bruno/notes/Create Media Note.yml
- bruno/notes/Update Media Note.yml
- bruno/progress/Update Reading Progress.yml
- bruno/user/admin/Register Admin User.yml
- bruno/user/auth/Logout User.yml
- bruno/user/auth/Refresh Token.yml

Improvements include:
- Consistent YAML structure and indentation
- Proper multiline string format for JSON bodies
- Moved auth: inherit after headers for consistency
- Added descriptive comments in request bodies

## Automation Features

Added runtime scripts to Create Library.yml:
- after-response script automatically extracts and saves library_id
  from API response to environment variables
- Persists library_id for use in subsequent requests
- Reduces manual copy-paste workflow during testing

Updated request bodies with example data:
- Create Media Item.yml: Added complete example with library_id
  variable reference, title, author, file_path, file_size, mime_type
- Other files: Updated with proper JSON formatting

## Benefits

- More consistent API collection structure
- Automated workflow reduces manual steps
- Better readability with proper YAML formatting
- Example data makes requests easier to understand

bruno/media-items/Update Media Rating.yml

@@ -11,7 +11,11 @@ http:
       value: application/json
   body:
     type: json
-    data: ""
+    data: |-
+      {
+        "rating": 9,
+        "review": "Updated review text"
+      }
   auth: inherit
 
 runtime: