Close the 0.9.3 UI polish milestone

Add deterministic captures 14-21 for the remaining screen-design states, fix the panel/button layout issues they exposed, and record 21/21 compare and judge results. Bump the source to 0.9.3 and move the completed milestone to DONE.md.

src/game/ui/radio_panel.gd

@@ -107,6 +107,7 @@ func _init() -> void:
 	var buttons := HBoxContainer.new()
 	vbox.add_child(buttons)
 	action_button = Button.new()
+	action_button.custom_minimum_size = Vector2(190, 0)
 	action_button.text = Strings.lookup("ui.radio_send_assist")
 	action_button.button_down.connect(func(): _start_hold())
 	action_button.button_up.connect(func(): _stop_hold(false))
@@ -114,6 +115,7 @@ func _init() -> void:
 	UiStyles.apply_button(action_button, 16)
 	buttons.add_child(action_button)
 	cancel_button = Button.new()
+	cancel_button.custom_minimum_size = Vector2(140, 0)
 	cancel_button.text = Strings.lookup("ui.radio_cancel")
 	cancel_button.pressed.connect(func(): cancelled.emit())
 	UiStyles.apply_button(cancel_button, 16)