Fix using statement and clarify path format documentation

Co-authored-by: BornToBeRoot <16019165+BornToBeRoot@users.noreply.github.com>

Author: Copilot

Source/NETworkManager.Settings/SettingsManager.cs

@@ -5,6 +5,7 @@
 using System;
 using System.IO;
 using System.Linq;
+using System.Security;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 using System.Xml.Serialization;
@@ -104,7 +105,7 @@ public static string GetSettingsFolderLocation()
                 {
                     Log.Error($"Policy-provided SettingsFolderLocation format is not supported: {policyPath}. Falling back to default location.", ex);
                 }
-                catch (System.Security.SecurityException ex)
+                catch (SecurityException ex)
                 {
                     Log.Error($"Insufficient permissions to access policy-provided SettingsFolderLocation: {policyPath}. Falling back to default location.", ex);
                 }

Website/docs/system-wide-policies.md

@@ -139,8 +139,8 @@ See [Location](./settings/settings.md#location) for more details.
 :::warning
 
 When configuring a custom settings folder location, ensure:
-- The path **must be an absolute path** (e.g., `C:\\Path\\To\\Folder`, not `.\\RelativePath`)
-- The path uses double backslashes (`\\`) in JSON format
+- The path **must be an absolute path** (e.g., `C:\\Path\\To\\Folder` or `C:/Path/To/Folder`, not `.\\RelativePath`)
+- For Windows paths, use either double backslashes (`\\`) or forward slashes (`/`) in JSON format (both `C:\\Path\\Folder` and `C:/Path/Folder` are valid)
 - The path does not contain invalid characters for the file system
 - The application has read/write permissions to the specified directory
 - The directory exists or the application has permissions to create it