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/books/Bulk Delete Books.bru

@@ -1,11 +1,11 @@
 meta {
-  name: Bulk Delete Books
+  name: Bulk Delete Media Items
   type: http
   seq: 1
 }
 
 post {
-  url: {{base_url}}/api/books/bulk-delete
+  url: {{base_url}}/api/media-items/bulk-delete
   body: json
   auth: inherit
 }
@@ -16,7 +16,7 @@ headers {
 
 body:json {
   {
-    "book_ids": [
+    "media_item_ids": [
       "{{bookId1}}",
       "{{bookId2}}",
       "{{bookId3}}"
@@ -31,7 +31,7 @@ script:post-response {
       const body = res.getBody();
       tests['Has results array'] = Array.isArray(body.results);
       tests['Has total count'] = body.total !== undefined;
-      tests['Has success count'] = body.success !== undefined;
+      tests['Has deleted count'] = body.deleted !== undefined;
       tests['Has failed count'] = body.failed !== undefined;
     } else {
       tests['Bulk delete failed'] = false;
@@ -46,23 +46,23 @@ settings {
 }
 
 docs {
-  ## Bulk Delete Books
+  ## Bulk Delete Media Items
 
-  Deletes multiple books in a single request.
+  Deletes multiple media items in a single request.
 
   **Method:** POST
 
-  **Endpoint:** /api/books/bulk-delete
+  **Endpoint:** /api/media-items/bulk-delete
 
   **Authentication:** Required (Bearer token)
 
   **Request Body:**
-  - `book_ids` (array of strings): Array of book UUIDs to delete
+  - `media_item_ids` (array of strings): Array of media item UUIDs to delete
 
   **Response:**
   - `results` (array): Results for each deletion attempt
-  - `total` (number): Total number of books processed
-  - `success` (number): Number of successfully deleted books
+  - `total` (number): Total number of media items processed
+  - `deleted` (number): Number of successfully deleted media items
   - `failed` (number): Number of failed deletions
 
   **Status Codes:**
@@ -75,7 +75,7 @@ docs {
   **Example:**
   ```json
   {
-    "book_ids": [
+    "media_item_ids": [
       "uuid-1",
       "uuid-2",
       "uuid-3"