chore(client): add gdUnit4 test framework addon

Vendor gdUnit4 for Godot 4 client testing (D-030).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/addons/gdUnit4/src/cmd/CmdOptions.gd

@@ -0,0 +1,31 @@
+class_name CmdOptions
+extends RefCounted
+
+
+var _default_options :Array[CmdOption]
+var _advanced_options :Array[CmdOption]
+
+
+func _init(p_options :Array[CmdOption] = [], p_advanced_options :Array[CmdOption] = []) -> void:
+	# default help options
+	_default_options = p_options
+	_advanced_options = p_advanced_options
+
+
+func default_options() -> Array[CmdOption]:
+	return _default_options
+
+
+func advanced_options() -> Array[CmdOption]:
+	return _advanced_options
+
+
+func options() -> Array[CmdOption]:
+	return default_options() + advanced_options()
+
+
+func get_option(cmd :String) -> CmdOption:
+	for option in options():
+		if Array(option.commands()).has(cmd):
+			return option
+	return null