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/highlights/Create Media Highlight.yml.bak

@@ -0,0 +1,41 @@
+info:
+  name: Create Media Highlight
+  type: http
+  seq: 2
+http:
+  method: POST
+  url: '{{base_url}}/api/media-items/{{media_item_id}}/highlights'
+  auth: inherit
+  body:
+    type: json
+    jsonBody: "{\n    \"selection_text\": \"This is the highlighted text from the\
+      \ media item.\",\n    \"start_position\": \"page:45:offset:120\",\n    \"end_position\"\
+      : \"page:45:offset:145\",\n    \"color\": \"#ffff00\",\n    \"note_id\": \"\""
+
+docs: |-
+  ## Create Media Highlight
+    
+    Creates a new highlight for a specific media item.
+    
+    **Method:** POST
+    
+    **Endpoint:** /api/media-items/:id/highlights
+    
+    **Path Parameters:**
+    - `id` (string): Media item ID
+    
+    **Request Body:**
+    - `selection_text` (string): Highlighted text (required, 1-5000 chars)
+    - `start_position` (string): Start position (required, max 100 chars)
+    - `end_position` (string): End position (required, max 100 chars)
+    - `color` (string): Highlight color in hex format (optional, default #ffff00)
+    - `note_id` (string): Optional associated note ID
+    
+    **Response:**
+    - Highlight object with all fields including generated ID and timestamps
+    
+    **Status Codes:**
+    - 201: Created
+    - 400: Invalid request
+    - 401: Unauthorized
+    - 404: Media item not found