sdb (GAMES) is an ssd - samsung 870 qvo, rotational=0 - so unlike the two wd
spinners there is no spin-down to gain from automounting it, and a steam library
is better off never sitting behind a trigger. keeps nofail. dump and bak stay
lazy.
splits the old dataDrive helper into spinningDrive and eagerDrive and documents
why each drive gets which.
also records the steam gotcha found while debugging "steam library folder not
writable": it was never a permissions problem - the drives are owned by uid 1000
mode 755 and were writable throughout. steam's fhs sandbox builds its bind list
at launch by iterating /*, and /mnt does not exist on nixos until these
fileSystems entries are activated, so a steam started before that has no /mnt
for its entire lifetime. restarting steam is the fix.
ahmza
a013737fbf