hark-store: crash on invalid note read
Two %read-note actions set on the same notification could cause the
cache to become invalid. Instead, crash if we read a note that is
already read.
&(=(read read.u.not) !?=(?(%read-note %unread-note) -.in))
~& >> "Inconsistent hark cache, rebuilding"
rebuild-cache
+ ?< &(=(read read.u.not) ?=(?(%read-note %unread-note) -.in))
=. u.tib
(~(put by u.tib) index u.not(read read))
=. notifications
