some kinda mediocre prompt

[hawkw]

it would be cool if you could type stuff into mycelium and get text back out. maybe eventually you could even run "commands".

this probably means the following:

• actual keyboard driver (see #358)
• reserve a line at the bottom of the framebuffer for the text the user is typing, and don't write logs there
• when scrolling logs, don't scroll that line. this is gonna be mildly annoying --- we probably want to change the logging code to write text to a text buffer, and use that to draw a screen, rather than scrolling the raw pixels. this would also let us scroll history.. (see #364)
• put keyboard text in a buffer and draw it, and clear it on carriage returns (eventually this could "run" a "command")
• actually add some shell commands: see #374