runtime: unify final delivery and startup preconditions

src/startup-preconditions.test.ts

@@ -0,0 +1,23 @@
+import { describe, expect, it } from 'vitest';
+
+import {
+  STARTUP_PRECONDITION_EXIT_CODE,
+  StartupPreconditionError,
+  isStartupPreconditionError,
+  resolveStartupFailureExitCode,
+} from './startup-preconditions.js';
+
+describe('startup preconditions', () => {
+  it('maps startup precondition errors to the non-restart exit code', () => {
+    const error = new StartupPreconditionError('legacy migration required');
+
+    expect(isStartupPreconditionError(error)).toBe(true);
+    expect(resolveStartupFailureExitCode(error)).toBe(
+      STARTUP_PRECONDITION_EXIT_CODE,
+    );
+  });
+
+  it('keeps generic startup failures on exit code 1', () => {
+    expect(resolveStartupFailureExitCode(new Error('boom'))).toBe(1);
+  });
+});