[ENHANCEMENT/FIX] Add extensions and optional fields parsing and fix class syntax parsing for typedefs.

[Starexify]

This PR adds correct parsing for optional and extensions in typedefs.

For example this snippet:

typedef TestTypedef = {
	var id:Int;
	var data:T;
	var ?version:Float;
}

typedef ExtendedTypedef = {
	> TestTypedef,
	var description:String;
}

The hscriptpolymod parser would complain (images below) about the unexpected > and ? symbols before, but now it parses correctly the extensions and optional fields like version.

Extra

Also fixes the class syntax parsing of typedefs

The example code:

typedef TypedefData = {
  public var artist:String;
  private var privates:String;
  //static var renders:Array<String>;
  var strings:Array<String>;
  final finals:Array<String>;
}

Before:

After:

_{static context doesnt work in typedefs so I didn't allow it to get parsed}