CBOR decode boundary: hydrate ops into class instances

[flyingrobots]

Migrated from Method backlog

GitHub Issues are now the live work tracker. Repository docs remain Method evidence.

Field	Value
Source backlog	docs/method/backlog/up-next/PROTO_cbor-op-hydration.md
Archived source	docs/archive/backlog/github-issue-migration-2026-06-01/docs/method/backlog/up-next/PROTO_cbor-op-hydration.md
Original lane	up-next
Original id	PROTO_cbor-op-hydration
Original legend	PROTO
Original feature	runtime-boundaries

Original backlog card

CBOR decode boundary: hydrate ops into class instances

Effort: M

Problem

Ops deserialized from CBOR are plain objects ({ type: 'NodeAdd', ... }).
They pass through the reducer via string dispatch but fail instanceof
checks. The decode boundary should hydrate plain objects into Op class
instances so the entire pipeline is class-native.

Where

CborPatchJournalAdapter or CborCodec — wherever patches are
decoded from bytes back into PatchV2 objects.

Hard gate

Golden blob round-trip: encode a patch with classes → decode → verify
class instances. Must produce identical CRDT state.

Source

Cycle 0009 retro, Slice 5 deferral.