## Summary
Follow-up to #20308. After that PR, production code no longer loads
mocked metadata when the user is unauthenticated. The remaining
mocked-metadata helpers (`useLoadMockedMetadata`,
`preloadMockedMetadata`) are now only consumed by Storybook decorators,
so move them next to the other testing-only utilities to make their
scope explicit and prevent accidental re-introduction of a runtime
dependency on mocks.
- `src/modules/metadata-store/hooks/useLoadMockedMetadata.ts`
→ `src/testing/hooks/useLoadMockedMetadata.ts`
- `src/modules/metadata-store/utils/preloadMockedMetadata.ts`
→ `src/testing/utils/preloadMockedMetadata.ts`
The three Storybook decorator imports
(`MockedMetadataLoadEffect`, `ObjectMetadataItemsDecorator`,
`WorkflowStepDecorator`) are updated to the new `~/testing/...` paths.
No runtime behavior change.
## Test plan
- [x] `npx oxlint --type-aware -c .oxlintrc.json` on touched files —
clean
- [x] `npx prettier --check` on touched files — clean
- [ ] CI: storybook, unit tests, e2e tests
