feat: add comprehensive Bruno API tests for annotations

- Add complete Bruno collection for notes API (5 endpoints)
- Add complete Bruno collection for highlights API (5 endpoints)
- Include detailed request/response documentation
- Add proper validation examples and error cases
- Support both media-items and ebook endpoint testing
- Add environment variable support for dynamic IDs

bruno/notes/Delete Media Note.bru

@@ -0,0 +1,42 @@
+meta {
+  name: Delete Media Note
+  type: http
+  seq: 5
+}
+
+delete {
+  url: {{base_url}}/api/media-items/{{media_item_id}}/notes/{{note_id}}
+  body: none
+  auth: inherit
+}
+
+script:post-response {
+  onResponse(res);
+}
+
+settings {
+  encodeUrl: true
+  timeout: 0
+}
+
+docs {
+  ## Delete Media Note
+  
+  Deletes a specific note.
+  
+  **Method:** DELETE
+  
+  **Endpoint:** /api/media-items/:id/notes/:noteId
+  
+  **Path Parameters:**
+  - `id` (string): Media item ID
+  - `noteId` (string): Note ID
+  
+  **Response:**
+  - 204 No Content on success
+  
+  **Status Codes:**
+  - 204: Success
+  - 401: Unauthorized
+  - 404: Note not found
+}