JS: Add textbox module

applications/system/js_app/examples/apps/Scripts/textbox.js

@@ -0,0 +1,24 @@
+let textbox = require("textbox");
+
+// Set config before setting text
+// Focus (start / end), Font (text / hex)
+textbox.setConfig("end", "text");
+
+let text = "Example dynamic updating textbox\n";
+textbox.setText(text);
+
+// Non-blocking, can keep updating text after, can close in JS or in GUI
+textbox.show();
+
+let i = 0;
+while (textbox.isOpen() && i < 20) {
+    print("console", i++);
+    text += "textbox " + to_string(i) + "\n";
+    textbox.setText(text);
+    delay(500);
+}
+
+// If not closed by user (instead i < 20 is false above), close forcefully
+if (textbox.isOpen()) {
+    textbox.close();
+}