Introduces MojangAPI utility for handling skin uploads, cape management, and username changes via new backend endpoints. Updates Program.cs to support new IPC commands for skin selection, uploading, cape toggling, and username changes. Refactors frontend (logged.js, logged.html, logged.css) to provide UI for skin uploads, cape selection, and username changes, including new styles and blank cape asset. Refactors UserRecord to allow username mutation.
Introduces a cosmetics section in the profile with articles for username, capes, and skin. Adds UI for changing username, including input and button, and updates related CSS for styling. JS now shows the profile frame on initialization.
