feat(ql3): establish 3.0 incubation baseline

back/runtime/ports/localRunDispatchPlanSource.ts

@@ -0,0 +1,20 @@
+import type { ExecutionContext, ExecutionSpec } from '../domain/execution';
+import type { RunDispatchCandidate } from '../domain/runDispatchCandidate';
+
+export interface LocalRunDispatchPlan {
+  executionSpec: ExecutionSpec;
+  context: ExecutionContext;
+  logArtifactId?: string;
+  /** Optional non-blocking cleanup for attempt-scoped local resources. */
+  dispose?: () => void | Promise<void>;
+}
+
+/**
+ * Trusted local materializer. Implementations must resolve the pinned Task
+ * revision and create fresh Attempt-scoped output and Secret capabilities.
+ */
+export interface LocalRunDispatchPlanSource {
+  prepare(
+    candidate: Readonly<RunDispatchCandidate>,
+  ): Promise<LocalRunDispatchPlan | null>;
+}