Move the log popup to the main window

The quiz reports point changes with an event_logged signal, and the main
window adds them to the log. Alt+L is handled by the main window.

Quiz.tscn

@@ -4,7 +4,6 @@
 [ext_resource type="PackedScene" uid="uid://ds15cgsf8vpvc" path="res://MusicPlayer.tscn" id="5_emn36"]
 [ext_resource type="PackedScene" uid="uid://cdy4kvemwaiom" path="res://new_character_select.tscn" id="6_dhrvg"]
 [ext_resource type="PackedScene" uid="uid://dldpeo5y3l5hq" path="res://SettingsWindow.tscn" id="11_k62u5"]
-[ext_resource type="PackedScene" uid="uid://bijh5h5yrivm3" path="res://Log.tscn" id="14_26rwn"]
 [ext_resource type="PackedScene" uid="uid://cxlsmxnrp0agh" path="res://WinnerWindow.tscn" id="17_winner_window"]
 [ext_resource type="PackedScene" path="res://MusicListPanel.tscn" id="scene_MusicListPanel"]
 [ext_resource type="PackedScene" path="res://PlayersPanel.tscn" id="scene_PlayersPanel"]
@@ -130,15 +129,6 @@ horizontal_alignment = 1
 vertical_alignment = 1
 autowrap_mode = 2
 
-[node name="Log" parent="." unique_id=1289881388 instance=ExtResource("14_26rwn")]
-unique_name_in_owner = true
-visible = false
-layout_mode = 1
-offset_left = 562.0
-offset_top = 132.0
-offset_right = 1262.0
-offset_bottom = 832.0
-
 [node name="SongLoader" type="Node" parent="." unique_id=1520867349]
 script = ExtResource("song_loader_script")