feat: sprint 1 — auth + CRUD engagements

Ship the first feature end-to-end on the UI: users log in with JWT,
admins manage user accounts, and any authenticated user (per RBAC)
can create, list, view, edit, and delete engagements.

Backend (Flask + SQLAlchemy + SQLite, 63 pytest)
- User / Engagement models, Alembic 0001 initial schema
- argon2 password hashing, JWT bearer (60-min TTL), @login_required
  and @role_required decorators
- 13 API endpoints under /api/*, including last-admin protection on
  DELETE/PATCH user and JSON 404 on unknown /api/* paths
- `flask create-admin` CLI with duplicate / short-password handling

Frontend (React + Vite + Tailwind + TanStack Query, 20 vitest)
- Inter font bundled locally (no CDN), DESIGN.md tokens in Tailwind
- LoginPage / EngagementsList / EngagementForm / EngagementDetail /
  UsersAdmin pages with role-aware UI
- Layout, ProtectedRoute, StatusBadge, FormField, LoadingState,
  ErrorState, EmptyState, Toast + provider
- Axios client: Bearer interceptor, 401 → purge + /login + "Session
  expirée" toast, 403 → "Accès refusé" toast (declarative <Navigate>
  for already-authed users, Fragment-keyed admin user rows)

Deployment
- Single multistage Dockerfile (node:20-alpine → python:3.12-slim)
- docker/entrypoint.sh runs `flask db upgrade` before `flask run`
- Makefile: build/start/stop/restart/update/logs/create-admin/
  update-mitre/test-{backend,frontend,e2e}/clean
- .env.example documenting MIMIC_JWT_SECRET / MIMIC_DB_PATH / MIMIC_PORT
- SQLite at /data/mimic.sqlite on named volume mimic-data

Acceptance suite (Playwright, 36 tests, all 27 ACs)
- e2e/ scaffold with playwright.config + auth/api fixtures
- One spec per user story (us1-bootstrap through us6-deployment)
- Portable via MIMIC_CONTAINER_CMD / MIMIC_BASE_URL (docker or podman)

Docs
- README.md with quick-start and architecture overview
- CHANGELOG.md updated with Sprint 1 deliverables
- pyrightconfig.json so the Python LSP sees backend/.venv and
  resolves the `backend.app.*` absolute imports

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/src/App.tsx

@@ -0,0 +1,47 @@
+import { Navigate, Route, Routes } from 'react-router-dom';
+import { Layout } from '@/components/Layout';
+import { ProtectedRoute } from '@/components/ProtectedRoute';
+import { ToastViewport } from '@/components/Toast';
+import { LoginPage } from '@/pages/LoginPage';
+import { EngagementsListPage } from '@/pages/EngagementsListPage';
+import { EngagementFormPage } from '@/pages/EngagementFormPage';
+import { EngagementDetailPage } from '@/pages/EngagementDetailPage';
+import { UsersAdminPage } from '@/pages/UsersAdminPage';
+
+/**
+ * Router. Auth + role gates handled by <ProtectedRoute />.
+ * Default `/` redirects to /engagements (guarded — kicks to /login if no token).
+ */
+export function App(): JSX.Element {
+  return (
+    <>
+      <Routes>
+        <Route path="/login" element={<LoginPage />} />
+
+        {/* All authenticated routes share the Layout chrome. */}
+        <Route element={<ProtectedRoute />}>
+          <Route element={<Layout />}>
+            <Route path="/" element={<Navigate to="/engagements" replace />} />
+            <Route path="/engagements" element={<EngagementsListPage />} />
+            <Route path="/engagements/:id" element={<EngagementDetailPage />} />
+
+            {/* redteam + admin write actions */}
+            <Route element={<ProtectedRoute roles={['admin', 'redteam']} />}>
+              <Route path="/engagements/new" element={<EngagementFormPage />} />
+              <Route path="/engagements/:id/edit" element={<EngagementFormPage />} />
+            </Route>
+
+            {/* admin-only routes */}
+            <Route element={<ProtectedRoute roles={['admin']} />}>
+              <Route path="/admin/users" element={<UsersAdminPage />} />
+            </Route>
+          </Route>
+        </Route>
+
+        <Route path="*" element={<Navigate to="/" replace />} />
+      </Routes>
+
+      <ToastViewport />
+    </>
+  );
+}