Custom prefixes get symbols and scrambled text

Key changes

• Your custom prefix can now use decorative symbols like ★ ❤ ➤ ⚔ ♛, added from a new symbol picker in the website prefix editor.
• Search the picker by name, like "star", "heart" or "crown", then click a symbol to add it where your cursor is.
• Scrambled text is new too: select part of your prefix and press the Obfuscated button to make it scramble in game.
• The preview shows scrambled text moving the way it does in game, so you see the real look before you save.
• End the scrambled part before the end of your prefix so your name stays readable; the editor tells you if you forget.