feat(packs): ADR-0127.1+0127.2 — en_units_v1 + loader
Exhaustive units pack: 13 dimensions (7 base + 6 derived), ~150 unit
lemmas, ~25 containers, ~80 conversion edges (within-dimension
exhaustive, NIST/ISO sourced), affine temperature offsets, multi-
word structural rules.
Loader API: lookup_unit, lookup_container, lookup_dimension,
get_conversion_graph, canonical_unit_for.
Ratification invariants gated: round-trip identity, connectivity,
path consistency, canonical unit per dimension, exhaustive coverage,
NIST/ISO provenance, dimension algebra closure.
No parser/solver changes (deferred to 0127.3-0127.7).
04eb5626ea