Fix exception handling for LocalSettingsManager and path validation

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

Author: Copilot

Source/NETworkManager.Settings/LocalSettingsManager.cs

@@ -101,12 +101,20 @@ public static void Load()
                 {
                     Current = JsonSerializer.Deserialize<LocalSettingsInfo>(jsonString, JsonOptions);
 
-                    Log.Info("Local settings loaded successfully.");
-
-                    // Reset change tracking
-                    Current.SettingsChanged = false;
-
-                    return;
+                    // Check if deserialization returned null (e.g., file contains "null")
+                    if (Current == null)
+                    {
+                        Log.Warn("Local settings deserialized to null, initializing new local settings.");
+                    }
+                    else
+                    {
+                        Log.Info("Local settings loaded successfully.");
+
+                        // Reset change tracking
+                        Current.SettingsChanged = false;
+
+                        return;
+                    }
                 }
             }
             catch (Exception ex)

Source/NETworkManager.Settings/SettingsManager.cs

@@ -151,7 +151,7 @@ private static string ValidateSettingsFolderPath(string path, string pathSource,
         // Validate that the path doesn't contain invalid characters
         try
         {
-            // This will throw ArgumentException, NotSupportedException, or SecurityException if the path is invalid
+            // This will throw ArgumentException, NotSupportedException, SecurityException, PathTooLongException, or IOException if the path is invalid
             var fullPath = Path.GetFullPath(path);
 
             // Check if the path is a directory (not a file)
@@ -178,6 +178,16 @@ private static string ValidateSettingsFolderPath(string path, string pathSource,
             Log.Error($"Insufficient permissions to access {pathSource} SettingsFolderLocation: {path}. Falling back to {fallbackMessage}.", ex);
             return null;
         }
+        catch (PathTooLongException ex)
+        {
+            Log.Error($"{pathSource} SettingsFolderLocation path is too long: {path}. Falling back to {fallbackMessage}.", ex);
+            return null;
+        }
+        catch (IOException ex)
+        {
+            Log.Error($"{pathSource} SettingsFolderLocation caused an I/O error: {path}. Falling back to {fallbackMessage}.", ex);
+            return null;
+        }
     }
 
     /// <summary>

Source/NETworkManager/App.xaml.cs

@@ -87,7 +87,22 @@ by BornToBeRoot
         PolicyManager.Load();
 
         // Load (or initialize) local settings
-        LocalSettingsManager.Load();
+        try
+        {
+            LocalSettingsManager.Load();
+        }
+        catch (IOException ex)
+        {
+            Log.Error("Could not load local settings due to an I/O error! Using default local settings.", ex);
+        }
+        catch (UnauthorizedAccessException ex)
+        {
+            Log.Error("Could not load local settings due to insufficient permissions! Using default local settings.", ex);
+        }
+        catch (JsonException ex)
+        {
+            Log.Error("Could not load local settings! Local settings JSON is corrupted or invalid. Using default local settings.", ex);
+        }
 
         // Load (or initialize) settings
         try