New controls, main view

src/Library/TerminalUI/Models/Option.cs

@@ -0,0 +1,13 @@
+namespace TerminalUI.Models;
+
+public readonly ref struct Option<T>
+{
+    public readonly T Value;
+    public readonly bool IsSome;
+
+    public Option(T value, bool isSome)
+    {
+        Value = value;
+        IsSome = isSome;
+    }
+}