refactor(bruno): migrate API tests to Bruno DSL format

- Convert all existing .bru files from JSON to Bruno DSL format
- Remove obsolete files (conflicts/api.bru, kobo/Kobo Initialization.bru)
- Update auth configuration to use 'inherit' instead of explicit bearer tokens
- Add comprehensive documentation to all test files
- Improve test scripts with proper assertions and error handling

bruno/universal-progress/Update Universal Progress.bru

@@ -1,12 +1,22 @@
 meta {
-  name: "Update Universal Progress"
-  type: "http"
+  name: Update Universal Progress
+  type: http
   seq: 2
 }
 
 post {
-  url: "{{baseUrl}}/api/progress/{{mediaItemId}}"
-  body: {
+  url: {{baseUrl}}/api/progress/{{mediaItemId}}
+  body: json
+  auth: inherit
+}
+
+headers {
+  Authorization: Bearer {{jwt}}
+  Content-Type: application/json
+}
+
+body:json {
+  {
     "source": "web",
     "location": {
       "percentage": 0.45,
@@ -18,16 +28,59 @@ post {
       "user_agent": "integration-test"
     }
   }
-  headers: {
-    Authorization: "Bearer {{jwt}}"
-    Content-Type: "application/json"
-  }
 }
 
-tests {
-  assertions {
-    assert response.status == 200
-    assert response.body.sync_status == "success"
-    assert response.body.progress_updated == true
+script:post-response {
+  function onResponse(res) {
+    if (res.getStatus() === 200) {
+      const body = res.getBody();
+      tests['Sync status success'] = body.sync_status === "success";
+      tests['Progress updated'] = body.progress_updated === true;
+    }
   }
+  onResponse(res);
+}
+
+settings {
+  encodeUrl: true
+  timeout: 0
+}
+
+docs {
+  ## Update Universal Progress
+
+  Updates universal reading progress for a media item from a specific device or source.
+
+  **Method:** POST
+
+  **Endpoint:** /api/progress/{mediaItemId}
+
+  **Authentication:** Bearer token
+
+  **Path Parameters:**
+  - `mediaItemId` (string): Media item UUID
+
+  **Request Body:**
+  - `source` (string): Source identifier (web, kobo, koreader, device_id)
+  - `location` (object): Progress location data
+    - `percentage` (number): Progress percentage (0-1)
+    - `page` (number, optional): Current page
+    - `total_pages` (number, optional): Total pages
+    - `epubcfi` (string, optional): EPUB location
+    - `chapter` (number, optional): Current chapter
+  - `device_metadata` (object): Device metadata
+    - `device_type` (string): Device type
+    - `user_agent` (string, optional): User agent string
+
+  **Response:**
+  - `sync_status` (string): Sync status (success, partial)
+  - `progress_updated` (boolean): Whether progress was updated
+  - `conflicts_detected` (array, optional): Any conflicts detected
+
+  **Status Codes:**
+  - 200: Success
+  - 400: Invalid request data
+  - 401: Unauthorized
+  - 404: Media item not found
+  - 500: Internal server error
 }