# US02-05 — Build the Static Application Shell

Epic: [E02](../E02-unified-workflow-shell.md)

As a user, I want a fast, navigable application shell so all workflow views share one
consistent interface without server-generated operational HTML.

## Acceptance criteria

- `index.html`, CSS, and modular JavaScript are separate static files.
- Shared API client, store, router, error handling, cancellation, and SSE/polling
  adapters are implemented.
- Navigation routes restore current view and filters after reload.
- HTML fallback never intercepts `/api/v1` requests.

## Automated tests

- JavaScript tests cover API errors, store transitions, routing, and event fallback.
- Browser tests assert asset loading, deep links, reload, JSON-only APIs, and no
  unexpected console/network errors.

## Dependencies

- US02-04