refactor: standardize Bruno API requests with bruToJsonV2 format

- Convert all JSON tests to JavaScript functions for bruToJsonV2 compatibility
- Update authentication to use 'inherit' instead of manual headers
- Fix hardcoded URLs to use {{base_url}} variables
- Standardize variable syntax from {{ _.var }} to {{var}}
- Add comprehensive API documentation to all requests
- Update environment variables with missing required fields
- Apply consistent structure: meta, http method, headers, tests, vars, settings, docs
- Enhanced validation with proper error handling and field checks

bruno/library/Update Scan Settings.bru

@@ -4,6 +4,92 @@ meta {
   seq: 1
 }
 
+put {
+  url: {{base_url}}/api/library/scan-settings
+  auth: inherit
+  body: json
+}
+
+headers {
+  Content-Type: application/json
+}
+
+body:json {
+  {
+    "scan_frequency_minutes": 60,
+    "auto_scan_enabled": true
+  }
+}
+
+tests {
+  test_update_scan_settings_success(status, headers, body) {
+    if (status !== 200) {
+      throw new Error("Expected status 200, got " + status);
+    }
+
+    const contentType = headers["content-type"];
+    if (!contentType || !contentType.includes("application/json")) {
+      throw new Error("Expected content-type to contain application/json, got " + contentType);
+    }
+
+    // Verify response body is valid JSON and has expected structure
+    let data;
+    try {
+      data = JSON.parse(body);
+    } catch (e) {
+      throw new Error("Response body is not valid JSON");
+    }
+
+    if (!data || typeof data !== "object") {
+      throw new Error("Expected response body to be an object");
+    }
+
+    // Check for success message or updated settings
+    if (!data.message && typeof data.scan_frequency_minutes !== "number") {
+      throw new Error("Response missing expected fields");
+    }
+
+    return true;
+  }
+}
+
+settings {
+  encodeUrl: true
+  timeout: 0
+}
+
+docs {
+  ## Update Scan Settings
+
+  Updates user's library scanning settings.
+
+  **Method:** PUT
+
+  **Endpoint:** /api/library/scan-settings
+
+  **Authentication:** Required (Bearer token)
+
+  **Request Body:**
+  - `scan_frequency_minutes` (number, required): Minutes between automatic scans (1-1440)
+  - `auto_scan_enabled` (boolean, required): Whether automatic scanning is enabled
+  - `library_id` (string, optional): Specific library ID to update (if not provided, updates global)
+
+  **Response:** Updated scan settings object
+  - `scan_frequency_minutes` (number): Updated frequency
+  - `auto_scan_enabled` (boolean): Updated enabled status
+  - `last_scan_at` (string, optional): Timestamp of last scan
+  - `next_scan_at` (string, optional): Timestamp of next scheduled scan
+  - `updated_at` (string): Timestamp of settings update
+
+  **Status Codes:**
+  - 200: Success
+  - 400: Invalid settings (frequency out of range)
+  - 401: Unauthorized
+  - 403: Forbidden (access denied)
+  - 404: Library not found (if library_id provided)
+  - 500: Internal server error
+}
+
 put {
   url: {{base_url}}/api/library/scan-settings
   body: json