feat: handle more commands and properly implement older ones

* fix parser tests
* write logs to file
* gracefully terminate program
* make viewport follow output
* properly handle channel nicks and display them in the sidepanel
* general refactors and fixes

ui/mainscreen/styles.go

@@ -35,6 +35,4 @@ var (
 			Border(lipgloss.NormalBorder(), true).
 			Width(ui.MainStyle.GetWidth() * 2 / 10).
 			BorderForeground(lipgloss.Color("#EEE"))
-
-	InputBoxHeight = 1
 )