decision(D-I): switch the wasm package and retire the freeze contract

[softmarshmallow]

Tracks registry decision D-I under #43. This issue is deliberately separate from D-E. No switch or freeze-contract retirement occurs without explicit owner GO and product-side coordination.

Decision question

What package identity, compatibility boundary, soak window, and coordinated unpin move the product from the frozen v1 @grida/canvas-wasm@0.91.0-canary.22 artifact to the chassis wasm build, and when may the freeze contract retire?

Decision time

Phase 6 only, after the v2 wasm target is implemented as priced work and the Phase 6 entry gates hold.

Evidence bar

• A complete wasm API/ABI and package-consumer inventory, including every gridaco/grida pin and expected compatibility break.
• A CI-built chassis wasm package tested against the relevant scoreboard suites and product integration tests.
• An explicit package-identity proposal, migration/rollback procedure, and owner for each side.
• A release candidate with a soak duration and success/failure thresholds fixed before the soak, plus observed results.
• A linked product-side unpin tracker using a full gridaco/grida#N reference before the decision.

Guardrails

• Never unpublish or deprecate @grida/canvas-wasm@0.91.0-canary.22.
• Until coordinated completion, the v1 package, v1-freeze, and format/grida.fbs remain untouched.
• D-I does not grant D-E bar flips, choose the v2 archive, or authorize unilateral engine-side or product-side switching.
• No new capability accretes to the frozen v1 package.

Context

• The consolidation program — one engine by extraction #43 — program position and Phase 6 gates
• The engine migration — history & the consolidation guideline (residue from gridaco/grida) #1 — freeze contract and product boundary
• chore: the engine split — the Rust engine moves to gridaco/nothing grida#988 — engine-split provenance
• decision(D-E): govern per-suite conformance-bar flips #57 — D-E, kept separate
• Product-side unpin tracker — must be filed and linked before decision

Done

The owner and product counterpart record GO; package identity, compatibility, soak, and rollback are documented; the chassis artifact ships and the product unpins with both repos green; the soak succeeds; freeze-contract retirement is recorded without removing or deprecating the pinned artifact; and the charter plus #43 are updated.