Add ColorPicker and FileSelector settings controls and API classes

src/DesktopMagicPluginAPI/Settings/FileSelector.cs

@@ -0,0 +1,65 @@
+namespace DesktopMagic.Api.Settings;
+
+/// <summary>
+/// Represents a file selector control that allows the user to browse for a file.
+/// </summary>
+public sealed class FileSelector : Setting
+{
+    private string _value = string.Empty;
+
+    /// <summary>
+    /// Gets or sets the selected file path.
+    /// </summary>
+    public string Value
+    {
+        get => _value;
+        set
+        {
+            if (_value != value)
+            {
+                _value = value;
+                ValueChanged();
+            }
+        }
+    }
+
+    /// <summary>
+    /// Gets or sets the file filter for the file dialog (e.g., "Image Files|*.png;*.jpg|All Files|*.*").
+    /// </summary>
+    public string Filter { get; set; }
+
+    /// <summary>
+    /// Gets or sets the title of the file dialog.
+    /// </summary>
+    public string Title { get; set; }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether the file selector should select folders instead of files.
+    /// </summary>
+    public bool SelectFolder { get; set; }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="FileSelector"/> class.
+    /// </summary>
+    /// <param name="defaultPath">The default file path.</param>
+    /// <param name="filter">The file filter for the file dialog.</param>
+    /// <param name="title">The title of the file dialog.</param>
+    /// <param name="selectFolder">If true, selects folders instead of files.</param>
+    public FileSelector(string defaultPath = "", string filter = "All Files|*.*", string title = "Select File", bool selectFolder = false)
+    {
+        _value = defaultPath;
+        Filter = filter;
+        Title = title;
+        SelectFolder = selectFolder;
+    }
+
+    internal override string GetJsonValue()
+    {
+        return Value;
+    }
+
+    internal override void SetJsonValue(string value)
+    {
+        Value = value;
+    }
+}