shift_mod(site_ref, delta)

shift_mod applies a Hilbert-aware wrapped shift.

This helper is intended for finite discrete local bases with contiguous, unit-spaced integer local_states. The builder records metadata so the lowerer can reproduce the same wrap semantics at runtime.

Use it when a degree of freedom should wrap around instead of saturating or leaving the basis.

Example:

plaquette = shift_mod("e0", +1).shift_mod("e1", -1)

Because wrapped semantics depend on the Hilbert local basis, shift_mod is more specialized than plain shift.