Local UTC Wall Clock
Policy time windows use the local UTC wall clock. They do not compensate for clock skew or supply a trusted/distributed time source.
Explicit Boundary
This is a deliberate design choice. If you need distributed time coordination, that's outside hp-guard's scope.
How It Works
The policy language supports closed UTC windows: start <= now < end (start inclusive, end exclusive).
For Deterministic Simulation
Callers can use the runtime's explicit-time resolution API for deterministic simulation and tests. The wall clock is the source of truth for policy evaluation — nothing more, nothing less.