e45640c4da
Consumer-layer cutover to worldtree-sdk (Python) 1.0.0: retire the hand-rolled httpx wrappers (sessions/sse_client/tier3) behind a thin ratatoskr.wt adapter over the SDK. Carries the 6 locked DECs (vor-cross'd with worldtree-codex), the route map (21 wrappers -> SDK methods), the Error map table (heid-panel find: route-as-discriminator, default -> SessionApiFailed), INV-CUT-1..5, and the 7-slice plan. Adapter design: caller-injected transport (never closed), thin semantic error adapter, Bifrost provider planes untouched. heid-contract-review clean after fixups (3/3 error-map convergence + 6 clarifications folded in). No version bump (.contract.md, no code). Refs #20.