Display free instead of used and with greater granularity if <1TiB

[fiveangle]

reporting used seems reasonable from a generic "disk info" standpoint, but the actual space available on each temp disk is really the only critical metric to plotter owners so we can see if we are getting too close to the edge

• swap reported raw used with free
• clarify % is % used
• report disk sizes with more granularity if <1TiB

example:

[cherymann]

tested and works on my system with the development branch

[cherymann]

tested and works on my system with the development branch

[creamsoup]

imo it should always display free. the free space is what we are interested. who cares how much it is used? fore those who cared should look at the farmer not plot manager. @swar, WDYT?

[fiveangle]

well, if anyone wants this, feel free to install from https://github.com/fiveangle/Swar-Chia-Plot-Manager/tree/critical_temp_disk_info . I'll keep that branch live until this PR is either merged or will maintain indefinitely if the PR here is rejected. If I can find the time, I really want to add the feature to send SIGSTOP signal to the last-launched plot job if free goes below a configurable threshold, then send SIGCONT to the process once free goes above that threshold again (+hysteresis padding), to prevent ruining the entire staggered pipeline if temp is cut too close on space, but I've been on a long road trip so no time 😬