import type { OrchestrationV2ThreadProjection, TurnItemId } from "@t3tools/contracts"; type Projection = OrchestrationV2ThreadProjection; export interface V2ItemSupport {  readonly item: Projection["turnItems"][number] | null;  readonly run: Projection["runs"][number] | null;  readonly attempts: ReadonlyArray<Projection["attempts"][number]>;  readonly node: Projection["nodes"][number] | null;  readonly providerSession: Projection["providerSessions"][number] | null;  readonly providerThread: Projection["providerThreads"][number] | null;  readonly providerTurn: Projection["providerTurns"][number] | null;  readonly runtimeRequest: Projection["runtimeRequests"][number] | null;  readonly checkpoint: Projection["checkpoints"][number] | null;  readonly subagent: Projection["subagents"][number] | null;  readonly contextHandoff: Projection["contextHandoffs"][number] | null;  readonly contextTransfer: Projection["contextTransfers"][number] | null;} export const EMPTY_V2_ITEM_SUPPORT: V2ItemSupport = Object.freeze({  item: null,  run: null,  attempts: Object.freeze([]),  node: null,  providerSession: null,  providerThread: null,  providerTurn: null,  runtimeRequest: null,  checkpoint: null,  subagent: null,  contextHandoff: null,  contextTransfer: null,}); /** * Resolves the relational V2 entities that enrich one projected item. The * caller supplies the item's source-thread projection, including for inherited * rows, so every returned entity retains its original projection identity. */export function resolveV2ItemSupport(projection: Projection, itemId: TurnItemId): V2ItemSupport {  const item =    projection.turnItems.find((candidate) => candidate.id === itemId) ??    projection.visibleTurnItems.find((candidate) => candidate.sourceItemId === itemId)?.item ??    null;  if (item === null) return EMPTY_V2_ITEM_SUPPORT;   const run =    item.runId === null      ? null      : (projection.runs.find((candidate) => candidate.id === item.runId) ?? null);  const attempts =    item.runId === null      ? EMPTY_V2_ITEM_SUPPORT.attempts      : projection.attempts.filter((candidate) => candidate.runId === item.runId);  const node =    item.nodeId === null      ? null      : (projection.nodes.find((candidate) => candidate.id === item.nodeId) ?? null);  const providerThread =    item.providerThreadId === null || item.providerThreadId === undefined      ? null      : (projection.providerThreads.find((candidate) => candidate.id === item.providerThreadId) ??        null);  const providerSession =    providerThread?.providerSessionId == null      ? null      : (projection.providerSessions.find(          (candidate) => candidate.id === providerThread.providerSessionId,        ) ?? null);  const providerTurn =    item.providerTurnId === null      ? null      : (projection.providerTurns.find((candidate) => candidate.id === item.providerTurnId) ??        null);  const requestId =    item.type === "approval_request" || item.type === "user_input_request"      ? item.requestId      : node?.runtimeRequestId;  const runtimeRequest =    requestId == null      ? null      : (projection.runtimeRequests.find((candidate) => candidate.id === requestId) ?? null);  const checkpoint =    item.type === "checkpoint"      ? (projection.checkpoints.find((candidate) => candidate.id === item.checkpointId) ?? null)      : null;  const subagent =    item.type === "subagent"      ? (projection.subagents.find((candidate) => candidate.id === item.subagentId) ?? null)      : null;  const contextHandoff =    item.type === "handoff"      ? (projection.contextHandoffs.find((candidate) => candidate.id === item.contextHandoffId) ??        null)      : null;  const contextTransfer =    contextHandoff?.transferId == null      ? null      : (projection.contextTransfers.find(          (candidate) => candidate.id === contextHandoff.transferId,        ) ?? null);   return {    item,    run,    attempts,    node,    providerSession,    providerThread,    providerTurn,    runtimeRequest,    checkpoint,    subagent,    contextHandoff,    contextTransfer,  };} function sameEntities<A>(left: ReadonlyArray<A>, right: ReadonlyArray<A>): boolean {  return left.length === right.length && left.every((value, index) => value === right[index]);} export function v2ItemSupportEqual(left: V2ItemSupport, right: V2ItemSupport): boolean {  return (    left.item === right.item &&    left.run === right.run &&    sameEntities(left.attempts, right.attempts) &&    left.node === right.node &&    left.providerSession === right.providerSession &&    left.providerThread === right.providerThread &&    left.providerTurn === right.providerTurn &&    left.runtimeRequest === right.runtimeRequest &&    left.checkpoint === right.checkpoint &&    left.subagent === right.subagent &&    left.contextHandoff === right.contextHandoff &&    left.contextTransfer === right.contextTransfer  );}