Follow the GDScript style guide in every script

- Types on every parameter, return value and variable, and snake_case names
  (the player name limit is the constant MAX_NAME_LENGTH).
- Spelling fixes: *_triggered, character_selected, separator, caught_errors.
  The server's catched_errors key stays as the server sends it.
- Signals are connected with signal.connect() instead of by name.
- Code is ordered signals, constants, exported vars, vars, @onready vars,
  functions, with @onready on one line and two blank lines between functions.
- Every script starts with a ## description. Template comments, old LOC notes
  and commented-out code are gone, apart from the local play code.
- Lines are at most 100 characters, apart from the local play path.
- The screenshot tour turns off the blinking text cursor so pictures match.

about_popup.gd

@@ -1,18 +1,8 @@
 class_name AboutPopup
 extends BasePopup
+## Shows the game version and what is new in each version.
 
-@onready
-var about_panel: Panel = %AboutPanel
-
-@onready
-var version_label: Label = %VersionLabel
-
-@onready
-var whats_new_label: Label = %WhatsNewLabel
-
-
-
-# Changelog as Dictionary with version as key and description as value
+## What is new in each version, newest first.
 const WHATS_NEW: Dictionary = {
 	"1.9.0": "Made improvements to the Search window
 	Made small changes to the inspiration list scrolling
@@ -51,15 +41,19 @@ const WHATS_NEW: Dictionary = {
 	"0.7-Beta": "Can now hop between songs"
 }
 
+@onready var about_panel: Panel = %AboutPanel
+@onready var version_label: Label = %VersionLabel
+@onready var whats_new_label: Label = %WhatsNewLabel
+
 
 func open() -> void:
 	super()
 	version_label.text = Settings.version
-	
+
 	# Build changelog text with version headers
 	var changelog_text: String = ""
 	for version: String in WHATS_NEW.keys():
 		changelog_text += "\n" + version + "\n"
 		changelog_text += WHATS_NEW[version] + "\n"
-	
+
 	whats_new_label.text = changelog_text