Refresh d6/langgraph-python fixtures (beautiful-chat, chat-slots,
frontend-tools-async, gen-ui-{agent,custom,declarative,interrupt,open},
headless-complete, hitl-in-app, interrupt-headless, shared-state-streaming,
tool-rendering, tool-rendering-reasoning-chain, _from-feature-parity) plus
d4/langgraph-python/chat.json. Combined with the conveyance shim landed
in this branch, LGP is fixture-complete at 180 pass / 5 fail / 2 skip.
The residual 5 fails trace to react-core/v2's custom-wildcard-renderer
bug surfaced through gen-ui-interrupt (shared useInterrupt hook misbehaves
on the second interrupt; cross-integration D6 blocker, not a fixture or
conveyance defect). The 2 skips are the by-design mcp-apps iframe gap.
Adds per-integration D6 fixtures for langgraph-python, langgraph-typescript,
and langgraph-fastapi. Each fixture is keyed by match.context for cross-
integration isolation and uses hasToolResult:false on toolCall responses
to prevent re-match loops.
Jordan Ritter