Complete native slot identity and lifecycle snapshot parity

[fruwe]

Native runtime proposals now preserve their containing action locator and independent internal/external ordinals, including repeated/mixed sends and assignments before final completion. Grammar-only discovery keeps metadata and map data inert. Typed native environment sends target one configured component and validate its external variable declarations before mutation; all eight cases execute against actual component mailboxes and state.

Source compilation accepts only executable grammar slots, retains sealed version-1 source/manifest evidence even without a supplied manifest, and re-verifies each compiler immediately before invoking it. Historical source guarantees stay distinct from generated CEL runtime guarantees. A compiler rebinding regression prevents a substituted second-region entrypoint from executing. Safe inspection and restore use actual production resolvers.

Validated exact head: d1d626a15a909d176f915013d88c0fa7a6ba7597. Independent exact-head LGTM and all seven current-head CI checks passed (Python 3.11/3.13, PostgreSQL, lint/types/unit/conformance and clean distribution installation). Local gates: 505 unit tests passed (six PostgreSQL tests separately passed with the prepared service), 1083 conformance tests, all 52 runtime-provider adapter vectors, 46 authority responses/observations and 43 committed-effect vectors. Wheel and sdist built locally; no publication.

Exact pins: specification 77c0a2e60cd0771a6d44ae170a079ddd51d7d9f0, conformance c6949440f5b9fd6e06ea5571f4e01681dd59ee04. Preserves unreleased 0.3.0, version-1 contracts and numeric machine format 1. This PR completes this integration only; concrete timer/archive/recovery helpers, Rust effect parity, infrastructure lifecycle examples and the full publication audit remain open in the coordinated scope.

Closes #108