Resolve exact installed Domain Pack artifacts

[eamirian]

Summary

• promote the provider-free Domain Pack conformance runner to the production-safe ace.intelligence.packs.conformance boundary while preserving the existing ace.testing.domain_pack compatibility import
• add a host-only installed artifact resolver that indexes inert package data by the fixed domain_packs/<pack-id>/manifest.json shape without compiling or conforming unrelated Packs
• require exactly one fixed conformance/activation_golden_fixture.json for the requested Pack, then recompile and reconform only that Pack's declared bytes before returning an artifact
• resolve only an exact CompiledPackRefV1 match across pack ID, pack version, compiled-pack ID, and pack digest

Safety boundaries

The resolver never imports Domain Pack packages, inspects or executes entry points, or treats a distribution version as the Pack version. It rejects missing, malformed, substituted, symlinked, nonconformant, provenance-crossed, and duplicate Pack material. Duplicate Pack identities fail closed even when their bytes are identical.

The provider-free conformance interpreter lives on the pure ace.intelligence.conformance surface. Installed distribution discovery is an application/host concern exposed from ace.application.installed_pack_artifacts; it depends only on the standard library and public ace.* contracts and interpreters. No implementation lives under core.engine, and no boundary allowlist exception is added.

An installed distribution may carry several inert Packs at different readiness levels. Valid manifest identities are indexed together, while only the exact requested Pack is compiled and conformed. An unrelated Pack without an activation fixture does not block an exact valid activation; requesting that unready Pack still fails closed.

Verification

• focused installed resolver, stable Domain Pack platform, and installed catalog tests: 19 passed
• Ruff and diff checks passed
• built ace_core-0.8.2-py3-none-any.whl
• installed the Core candidate wheel and World wheel together in a clean temporary Python 3.12 environment; the resolver indexed all five World Pack manifests and exactly resolved/conformed world_intelligence_ai while unrelated Packs remained inert

Dependency

World Intelligence currently packages Pack manifests but does not yet package the required fixed conformance/activation_golden_fixture.json. Its installed Pack will therefore fail closed until the World repository adds one exact passing fixture and includes it as package data. This PR does not change World, activate a Pack, merge, publish, or release.