Releases all tracked pair states and resets the enter/stay/exit bookkeeping.
Solves all active contact pairs, then dispatches the resulting collision/trigger life-cycle events (enter/stay/exit) for this step.
Active collision pairs discovered this step (mutated in place).
Joints to solve during each PGS iteration and in the positional pass.
Per-step configuration and dependencies.
Iterative contact solver: penetration separation, normal/friction impulse resolution with angular response, trigger/collision bookkeeping and resting-contact stabilization.
Owns the per-frame pair state maps and the small object pool backing them, keeping the state lifecycle and the mathpool-discipline of the hot loop in one place. The broadphase pair discovery and spatial queries stay with the owner system; only the solve step is here.