F1 Test Drive Applicability (required before setup) This is the canonical F1 applicability policy. Inspect the actual diff against the PR base and identify the behavior that needs validation before starting F1, selecting a fixture, or creating a report. Task size, issue labels, filenames, and a generic request to verify/ship are not sufficient reasons to run F1. - Required: product/runtime changes exercised by F1 (issue tracking, authentication, routing, runner/session lifecycle, activity rendering), and functional changes to the F1 harness itself. Choose scenarios with assertions that exerci…