fix: reject incompatible Apple runtime companions

[leehack]

Summary

Closes #483. Prerequisite for draft release #482; this corrective PR does not prepare or publish a release.

Reject resolved Apple llama.cpp companions whose framework pin does not match the core before emitting LookupInProcess. Existing app constraints llamadart: ^0.8.22 with companion ^0.0.17 otherwise admit a v0.4.0 core patch while retaining v0.3.0 frameworks. This release-exposed defect was found before core0.8.23 publication; the name-only hook behavior predates the release-prep PR.

Exact scope

• Resolve the actual companion from the nearest consumer/workspace package_config version2, including relative percent-encoded roots and dependency/path overrides. Declared constraints do not authorize an ABI.
• Verify unique companion entry, package identity/version metadata, the complete maintained SwiftPM template and exact native v0.4.0 pin. The template digest normalizes only tag, one checksum and CRLF; arbitrary helper URL changes and decoy comments cannot authorize different binaries. Missing, malformed, duplicated or mismatched metadata fails with an actionable diagnostic before any process asset is emitted.
• Reject unverified companion Artifacts overrides rather than treating a tag string as proof of their binary ABI. Core native runtime/source/backend overrides cannot bypass the check.
• Declare consumer pubspec, package_config, resolved companion pubspec/Package.swift and Artifacts-directory cache dependencies. Canonical hooks_runner1.5.0 hashes missing directories and detects creation, preventing a later local override from inheriting a cached successful result.
• Use direct yaml dependency for real pubspec dependency parsing, covering flow syntax and nested keys. LiteRT-only, non-Apple and no-companion fallback behavior remain unchanged.
• No package version, native/Web/LiteRT pin, framework, generated binding, public engine API or publication workflow changed.

Validation

• Canonical Flutter3.47.1 / Dart3.13.1 workspace prep, whole format/analyze PASS.
• Real build-hook focused suite34/34 PASS: old0.0.17/v3 rejected on iOS/macOS despite overrides; supported0.0.18/v4 process lookup; missing/duplicate/malformed metadata, false new version, wrong target, hardcoded helper URL/decoy comments, local artifacts; workspace roots/cache dependencies; flow YAML/path override bypass; existing no-companion/nonApple/LiteRT-only/mixed contracts.
• Full VM2002 passed/77 fixture skips on the complete production correction; full Chrome925/925 PASS. Final test-only URI assertion portability correction revalidated in the focused34/34 suite.
• Platform import boundary, release docs verifier, Node20 website7tests/production build/strict links PASS.
• Live old published companion0.0.17 archive inspected: Package.swift pin is v0.3.0; archive SHA256 bffa3a62325c530ca3aa34f222f34f7670e81f67cc31ed410a93df7c8f680bf8. Tests exercise the maintained manifest with this incompatible identity through the actual hook.
• This is a pre-build compatibility check, not a new native runtime; no physical device rerun is claimed or needed to prove the rejected build branch. Existing Pixel qualification stays separate.

High-risk regression review

• Classification: high-risk artifactConsumer and regressionPolicy (the durable AGENTS guard rule); no existing readiness requirement was weakened.
• Implementation: isolated fix/apple-companion-abi-guard.
• Exact head 93966bf0268e20b83eb3348297ad1e1eeb44b0f3, base 9ed77aa12dbd6a6daef185a5bff7484b5a9a5f5f.
• Independent Astra QA: PASS on exact93966bf after correcting the initial loose Swift fragment bypass in603e2c1. Auditor independently reran34/34 actual-hook tests and verified unchanged/CRLF manifests plus altered URL/tag/helper/repository rejection. No remaining bounded blocker.
• Final exact-head hosted checks15/15 SUCCESS, CLEAN/MERGEABLE, zero total/unresolved review threads. CI: https://github.com/leehack/llamadart/actions/runs/34136399935 ; LiteRT: https://github.com/leehack/llamadart/actions/runs/34136399960 . PR remains draft.
• Canonical local high-risk evidence evaluator reports internally consistent evidence, but unverifiedPrerequisites / externalPrerequisitesUnavailable: repository-local tooling cannot authenticate the dedicated App/auditor/protected environment/ruleset. This known owner-controlled governance boundary is not bypassed and no operational attestation is claimed. Evidence: /private/tmp/appleguard-readiness.json.
• Production branch deletion/bypass proof: actual hook negative tests fail if validation is removed and process assets are emitted.
• Known PR-caused P1s: zero after fixes and independent final audit. This safely rejects mismatched consumer constraints; it does not automatically rewrite an existing application's dependencies.

No mark-ready, merge, tag, release, publication, workflow dispatch, settings or pin change was performed. Release#482 remains blocked until this prerequisite is reviewed and separately approved/merged, then integrated and requalified.

[github-actions]

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