Finally implemented the actual portfolio design! This includes a tab
mechanism for various aspects of the portfolio and the complete content
for the about tab.
Also fixes the TUI not being correctly scaled due to crossterm using the
dimensions of the server console tty instead of the client pty by
defining a custom `Backend` for ratatui.
Makes controls usable by taking SSH keystroke data (encoded in the xterm
format) and converting them to crossterm `KeyCode`s / `KeyEvent`s and
sending them to the `Tui`.
Also adds support for suspension of the `Tui` over the SSH connection.
Some minor refactoring was also done.