Completion date for objects with the done relation

Would be useful to have an in-built relation that stores when the checkbox was last checked (and possibly one that shows when it was last unchecked).

Pipe dream: allow enabling full history, recording every event (in case of multiple checks/unchecks).

Pipe dream plus: have every Object (and Relation) contain meta-Relations that record such events. Most users wouldn’t need to see/use this (this could be disabled by default). But could be very useful for certain situations.

Related: