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.

http_transport.gd

@@ -6,8 +6,8 @@ extends RefCounted
 
 ## Seconds before a request is given up and reported as failed. This covers the whole
 ## download, so it is generous enough for long songs on a slow connection.
-var timeout_seconds: float = 120.0
 
+var timeout_seconds: float = 120.0
 var _owner: Node