fix(review): apply code-review fixes — runId/foreachNodeId wiring, worktree-leak cleanup, rework re-execution, instance pruning, SIGKILL fallback, type dedup, board memo split, agent-native field-schema context + fn_workflow_get

17 findings from 12-reviewer code review applied:
- P1 runId trio (pin-probe/resume/markIntegrated used placeholder runId; 4-reviewer corroboration) + production-wiring tests
- P1 worktree/branch release on instance failure/exhaustion/abort
- P2 runGraphTaskStep no longer masks step-session failures; rejected memo cleared so rework re-executes
- P2 clearStaleInstanceStates wired at run start/end (mirrors branch pruning)
- P2 code-node timeout killSignal SIGKILL; dead template-recursion removed
- P1/P2 field-type re-declarations replaced with @fusion/core imports (stale comments removed)
- P2 Board memo split + TaskCard comparator stringify guard + modal prop-driven field defs
- HIGH agent-native: executor prompt injects custom-field schema/values; self-correcting rejection text; fn_workflow_get; fn_task_update bare-call guard; integration-conflict task log

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/engine/src/workflow-node-handlers.ts

@@ -81,6 +81,15 @@ export const FOREACH_ACTIVE_CONTEXT_KEY = "foreach:active";
  */
 export const SPLIT_ACTIVE_CONTEXT_KEY = "split:active";
 
+/**
+ * Reserved context marker (KTD-11) the worktree-isolation foreach seeds into an
+ * instance's context for ONE re-run after an integration-conflict, when the
+ * template authored an explicit `outcome:integration-conflict` edge. Author nodes
+ * read it to branch on the conflict; the sub-walk clears it after seeding so a
+ * later clean rework does not re-surface a stale conflict signal.
+ */
+export const INTEGRATION_CONFLICT_CONTEXT_KEY = "integration:conflict";
+
 /** Shape of the value stored under {@link FOREACH_ACTIVE_CONTEXT_KEY}. */
 export interface ForeachActiveContext {
   foreachNodeId: string;