Do not inhibit motion when Stopped is set.
We actually do need to move to move away the extruder from the bed, and
setting Stopped breaks it without adding any sort of security (M*
commands, such as M600 could still perform moves and still pass
through, while M104 would still set heaters).
During a hard error the internal queue is cleared (and sd file closed,
if any), so no new "unforeseen" command can be read.
Handle "Stopped" instead as a flag to inhibit serial processing and
automatically switch to "paused for user" state. While in this state
simply drop any input without incrementing the processed gcode line
number, behaving as-if the last command was still being processed.
This allows "Stopped" to correctly handle a printer-initiated paused
state and recover as expected by requesting a resend when resuming.
Add a new LCD_MESSAGE_INFO priority which can be overridden by regular
status updates, but only if a certain amount of time has passed.
Assign a time stamp to all message updates, so that the time since the
last update can be determined. Also switch the message type to Status,
so that the message always becomes visibile.
Always show status or info messages when printing via SD if the message
is recent enough.
Explicitly show which axes are affected on the status line when a crash
has been detected.
When the crash recovery prompt is triggered, also show all axes which
have been affected during the detection interval (currently X, Y, or
both).
The timer detection has been simplified to match the MK3 optical
filament timeout handling, which makes more sense: a crash immediately
following a crash recovery prompt will trigger the prompt again. The
timer needs to properly expire in order to reset the crash count.
This helps crash detection tuning (and help users reporting issues with
crash detection) without having to monitor the serial line.
This currently abuses the MSG_CRASH_DETECTED message by prepending the
[X][Y] labels to the message, which is ok in english but might not
translate that well for all languages.
