feat(lattice): add Enphase inventory fragment

[mgazza]

Summary

Add a pure, default-off Enphase complete-inventory Lattice fragment publisher on the generic
inventory seam from #4352.

The publisher accepts explicit complete site/device discovery snapshots for the closed inventory
kinds gateway, inverter, battery, and meter. It emits provider-local REFERENCE topology;
only an explicitly API-verified hardware serial can become a strong cross-provider identity.

This PR is stacked on #4352. It is unregistered and imports no live Enphase API, authentication,
endpoint, scheduler or control code.

Safety properties

• authority is 0; capabilities, roles, config projections, control claims and secrets are absent
• newer complete inventory replaces the provider-local view; omitted observations disappear
• explicit empty inventory is distinct from irreversible provider removal
• site/device ownership, membership, cardinality, health and generation rules are inherited from
  the common durable adapter boundary
• outer Enphase observations are reconstructed exactly before conversion; values that merely
  normalize to the canonical form fail before persistence or invalidation
• conversion uses unbound class methods, so instance-shadowed callbacks cannot inject topology or
  strong identity
• rejected or faulting input yields value-free errors with zero durable writes and invalidations
• streams consume at most maximum + 1; oversized and infinite inputs terminate

Validation

• focused Enphase boundary and hostile mutation tests on Python 3.9 and 3.14
• full non-control Lattice matrix on Python 3.9 and 3.14
• independent read-only adversarial review
• Black, Ruff, CSpell, pre-commit and staged diff checks
• GitNexus exact-worktree staged scope review

Not included

• no live Enphase discovery or polling
• no credentials, endpoints or auth state
• no auto-config materialization
• no schedule/control write
• no runtime registration or feature activation

Tracking: Predictive-Cloud-Ltd/predbat-saas-infra#561
Programme: Predictive-Cloud-Ltd/predbat-saas-infra#466