fix(cli): report reference-source import failures

src/cli/referenceSourceImportStatus.ts

@@ -0,0 +1,14 @@
+import { z } from "zod";
+
+import { isCliOperationFailure } from "../cliLogging.js";
+
+const referenceSourceImportFailureSchema = z.strictObject({
+  error: z.literal("Import failed"),
+  category: z.enum(["cancelled", "invalid_input", "execution_failure"]),
+  message: z.string().min(1),
+});
+
+/** Identify the historical-source import command's failed operation outputs. */
+export const isReferenceSourceImportCliFailure = (value: unknown): boolean =>
+  referenceSourceImportFailureSchema.safeParse(value).success ||
+  isCliOperationFailure(value);