Foundation for L10 resume-as-same-life persistence. Adds:
- core/array_codec.py: a leaf (numpy+base64) codec encoding arrays as
{dtype, shape, b64(raw bytes)} — BIT-EXACT, never decimal. Float round-trips
lose zero precision, so a restored versor keeps versor_condition < 1e-6 and a
replayed turn keeps its trace_hash. dtype carries byte order; float32 is never
conflated with float64.
- field/state.py: FieldState.to_dict/from_dict. Multivector arrays (F, holonomy)
go through the byte codec; energy/valence round-trip exactly via JSON-safe
helpers (lazy physics imports keep field/ cycle-free).
Exit gate (the scope's #1 risk, de-risked first): bit-exact round-trip AND
closure preserved — versor_condition(restored.F) == versor_condition(fs.F)
exactly. 10 codec/FieldState tests + 55 architectural-invariant/runtime tests
pass. Purely additive; no existing behavior changed.
Part of docs/analysis/L10-shapeBplus-persistence-scope-2026-06-05.md (Phase A).
