UI.9 Command line anywhere: docked in the status strip, floating over the drawing, in its own window, or hidden

Duncan docks a command line in the status strip (statusbar.command, 0.9 DU.1), and it only hands its text to the command finder; the reference screenshot floats one over the drawing with history above it and a ▾ to open the log. CadCraft has a real command line of its own (cad-cmdline-09.md) in the classic layout only. Change: a commandline block of its own (places: stage-bottom, bottom, float, window; options history, log, width), filled by the app when it has one (CadCraft's, with its LISP and keyword prompts) and by the finder elsewhere; dragged by its grip to float anywhere over the drawing or to a window (UI.2/UI.3), remembered; Ctrl+9 shows/hides it as people expect; typed input goes to it from anywhere in the drawing when the layout says so (the classic rule). Works in every layout the person adds it to (UI.5), default in Drafting (UI.12) and Duncan.