Beyond mount (component-children-test): drives real interactions on the compiled components and asserts state changes — Switch/Checkbox toggle, Accordion single-open, Tabs + SegmentedControl + Pagination controlled selection, CommandPalette filtering, Menu/Popover/Dialog/Drawer open+close (trigger, Escape, overlay/close-button), Form controller rules, plus a second batch — Tree select+expand, Splitter arrow-key resize, DatePicker calendar pick, ColorPicker swatch pick, TreeSelect leaf pick, and Sortable HTML5 drag-reorder. Loads _ds_bundle.js (regenerated at end of turn), so re-run on a fresh turn after editing component sources. window.__behavior.pass must be true. Hardened: React/bundle preflight, an 8s per-test watchdog and a 60s suite watchdog \u2014 the gate always publishes a verdict naming the stalled test instead of hanging (progress on window.__behaviorProgress).