Complete G0 AI-native foundation

[kyriewxcode]

What changed

• completes G0-02 application lifecycle/config contracts and G0-03 project/package/user path boundaries
• completes G0-04 by routing the existing Scene, Camera, Lighting, and Render Settings editor behavior through domain authoring services
• adds revision/change/evidence ledger contracts and typed v2 capability descriptors beside the existing legacy v1 handlers
• keeps rpc.discover at the same 35 method names and preserves existing UI, MCP JSON, Undo, rendering, asset, and persistence behavior
• updates CPU/static/runtime contract coverage and marks G0-01 through G0-04 Verified in the Spec registry and roadmap

Why

The existing editor exposed business rules through Panel/UI and MCP-specific paths. G0 requires those existing behaviors to share transport-neutral domain contracts, validators, revision tracking, and evidence without introducing new product features.

Impact

No new product feature, panel, gameplay path, Player target, or MCP method is introduced. Runtime/Shipping closure remains isolated from Developer, UI, MCP, and contract authoring code.

Validation

• Debug full build and CTest: 17/17 passed
• Release full build and CTest: 17/17 passed
• CPU Debug preset: 11/11 passed
• CPU Release preset: 11/11 passed
• Spec contracts: 9/9 concrete Specs passed
• RHI failure injection: expected exit 1 via quarantine
• clean lifecycle rerun: passed; no Error/Fatal/D3D12 validation log matches
• git diff --check: passed