test(bruno): add system settings API tests and update list users test

System Settings Bruno Tests (new):
- bruno/system/get-scan-settings.bru
- bruno/system/update-scan-settings.bru
- Test GET endpoint for retrieving system scan settings
- Test PUT endpoint for updating system scan settings
- Include admin authentication requirements
- Document response structures

List Users Bruno Test (update):
- bruno/user/admin/List Users.bru
- Add max_devices to response documentation
- Add device_count to response documentation
- Update feature descriptions

These Bruno tests provide API contract verification for the new
system settings endpoints and document the enhanced user list response.

bruno/system/get-scan-settings.bru

@@ -0,0 +1,30 @@
+meta {
+  name: Get System Scan Settings
+  type: http
+  seq: 1
+}
+
+get {
+  url: {{base_url}}/api/libraries/scan-settings
+  auth: inherit
+}
+
+headers {
+  Content-Type: application/json
+}
+
+script:post-response {
+  res.status.should.equal(200);
+  res.body.type.should.equal("application/json");
+  res.body.data.should.have.property('scan_frequency_minutes');
+  res.body.data.should.have.property('auto_scan_enabled');
+}
+
+docs {
+  ## Get System Scan Settings
+
+  Retrieves current system-wide scan settings for all libraries.
+
+  **Authentication**: Admin token required
+  **Response**: Current scan frequency and auto-scan status
+}

bruno/system/update-scan-settings.bru

@@ -0,0 +1,36 @@
+meta {
+  name: Update System Scan Settings
+  type: http
+  seq: 2
+}
+
+put {
+  url: {{base_url}}/api/libraries/scan-settings
+  body: json
+  auth: inherit
+}
+
+headers {
+  Content-Type: application/json
+}
+
+body:json {
+  "scan_frequency_minutes": 30,
+  "auto_scan_enabled": true
+}
+
+script:post-response {
+  res.status.should.equal(200);
+  res.body.type.should.equal("application/json");
+  res.body.should.have.property('message');
+}
+
+docs {
+  ## Update System Scan Settings
+
+  Updates system-wide scan settings that apply to all libraries.
+
+  **Authentication**: Admin token required
+  **Request**: Scan frequency (15-1440 minutes) and enabled status
+  **Response**: Success message
+}

bruno/user/admin/List Users.bru

@@ -34,6 +34,8 @@ docs {
   - `last_name` (string): Last name (empty if not set)
   - `role` (string): User role ("user" or "admin")
   - `theme` (string): Theme preference (empty if default)
+  - `max_devices` (integer): Maximum number of devices allowed
+  - `device_count` (integer): Current number of registered devices
   - `created_at` (string): Creation timestamp (ISO 8601)
   - `updated_at` (string): Last update timestamp (ISO 8601)
   
@@ -45,6 +47,7 @@ docs {
   **Features:**
   - Admin-only endpoint with complete user information
   - Returns first_name, last_name, role, theme fields
+  - Includes device limits and current device count
   - Useful for user management interfaces
 }
 
@@ -78,6 +81,8 @@ docs {
   - `last_name` (string): Last name (empty if not set)
   - `role` (string): User role ("user" or "admin")
   - `theme` (string): Theme preference (empty if default)
+  - `max_devices` (integer): Maximum number of devices allowed
+  - `device_count` (integer): Current number of registered devices
   - `created_at` (string): Creation timestamp (ISO 8601)
   - `updated_at` (string): Last update timestamp (ISO 8601)
   
@@ -89,5 +94,6 @@ docs {
   **Enhanced Features:**
   - Now admin-only endpoint (moved from public to protected admin group)
   - Returns complete user profile information including names and role
+  - Includes device limits and current device count for monitoring
   - Useful for comprehensive admin user management
 }