Constant MAX_TRIAL_DURATION 

pub const MAX_TRIAL_DURATION: Duration;

The default ceiling on the wall clock one segmented trial may consume.

SegmentedObjective::timeout bounds a single oniro run (or the eval after it). It does not bound the chain, and the chain is the resource: a plan may hold up to MAX_SEGMENTS segments, each costing a train and a metric operation, so a per-operation timeout of one hour already permits a single trial to occupy a machine for roughly a thousand years. A per-run timeout is not a per-plan budget.

Seven days is the number because it is more than an order of magnitude above the longest legitimate single trial this harness drives — an oniro RL run of a few million environment steps finishes in hours — while being five orders of magnitude below what an uncapped maxed-out chain would allow. The study’s own Budget::deadline_millis is the study bound and stops new trials at ask time; it cannot end a chain already inside one objective call, which is exactly the gap this closes.