test(bruno): update API tests for /api/media-items/ endpoints

- Update bulk-delete test: endpoint URL, request field (book_ids → media_item_ids), response field (success → deleted), documentation
- Update bulk-update test: endpoint URL, request structure (updates → media_item_updates), response field (success → updated), documentation
- Update download test: endpoint URL (/api/books/ → /api/media-items/), documentation

bruno/media-items/EPUB Download.bru

@@ -1,11 +1,11 @@
 meta {
-  name: Download EPUB Book
+  name: Download Media Item
   type: http
   seq: 1
 }
 
 get {
-  url: {{baseURL}}/api/books/{{bookUUID}}/download
+  url: {{baseURL}}/api/media-items/{{bookUUID}}/download
   body: none
   auth: none
 }
@@ -16,27 +16,27 @@ settings {
 }
 
 docs {
-  ## Download EPUB Book
+  ## Download Media Item
 
-  Download an EPUB book file from Bookhoard server. No authentication required for Kobo device downloads.
+  Download a media item file (EPUB, PDF, etc.) from Bookhoard server.
 
   **Method:** GET
 
-  **Endpoint:** /api/books/{bookUUID}/download
+  **Endpoint:** /api/media-items/{bookUUID}/download
 
   **Authentication:** None (for Kobo device downloads)
 
   **Path Parameters:**
-  - `bookUUID` (string): Book UUID
+  - `bookUUID` (string): Media item UUID
 
-  **Response:** Binary EPUB file data
+  **Response:** Binary file data (EPUB, PDF, etc.)
 
   **Response Headers:**
-  - `Content-Type`: application/epub+zip
+  - `Content-Type`: application/epub+zip, application/pdf, or appropriate MIME type
 
   **Status Codes:**
-  - 200: Success - EPUB file returned
-  - 404: Book not found
+  - 200: Success - File returned
+  - 404: Media item not found
 
-  **Note:** This endpoint is designed for Kobo devices to download books directly from Bookhoard. The endpoint returns the book file with appropriate Content-Type headers.
+  **Note:** This endpoint is designed for Kobo devices to download media items directly from Bookhoard. The endpoint returns the file with appropriate Content-Type headers.
 }