#468 Forensics test: give the late collector real slack

Accepted agent delivery; branch-keyed search descriptor included.

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Summary by cubic

Fixes the forensics timeout test so it only fails on a real hang, not on a loaded runner's late wake-up. The collector now gets a ~100 ms deadline with ~20 s of outer slack instead of a 300 ms margin, preventing false failures from overrun sleep waking late.

• Adds benchmarks/aft-search/slice-descriptors/land-forensics-margin-test.json to describe the slice used by this test.

Confidence Score: 5/5

The PR appears safe to merge.

Summary

Gives the late-collector test more time to return its report on a busy runner.

• The late-collector test leaves more time for its report.

_{Reviews (1) · Last reviewed commit: "landing: describe forensics-margin-test" · Reviewed by Greptile}