P1 complete: web front, test suite, CI — acceptance ALL GREEN

Fan-out integration + fixes found by the test/acceptance pass:
- FIX ring-buffer: chunks >= capacity skipped bytes now count into the
  monotonic offset (invariant: stream byte k lives at k % capacity) —
  window order was corrupted on unaligned big chunks
- FIX auth: non-numeric cookie expiry no longer bypasses expiration
- FIX protocol: safe-integer validation on ack.bytes / hello.protocol
- FIX @fastify/websocket v11: websocket route must be registered in an
  encapsulated context after plugin load (handler got REST signature)
- FIX flow-control deadlock found by e2e acceptance: client only ACKs
  on data receipt, so pausing with an unACKed residue in (LOW,
  ACK_EVERY] stalled both sides at 0.9 MB. ACK_EVERY now 64 KiB (<=
  LOW invariant, tested) + trailing debounced ACK in the web client
- Web: Vue 3 + Vite + Pinia + Tailwind 4 + vue-i18n (EN/FR) + xterm 6
  (fit + webgl fallback), multiplexed ws-client with reconnect/backoff
  and resync epochs
- Tests: 100 vitest (protocol fuzz, ring edges, auth, pty-manager flow
  control with mocked pty, REST e2e) ; CI Node 22/24 + pack-smoke
- scripts/acceptance-p1.mjs: real daemon + real WS client — boot,
  login, attach, stdin, 10 MB flood w/ ACK (13.7 MB/1.9s, RSS bounded),
  brutal disconnect + replay resync, kill broadcast, SIGTERM drain

packages/web/src/router/index.ts

@@ -0,0 +1,20 @@
+import { createRouter, createWebHistory } from 'vue-router';
+import { useAuthStore } from '../stores/auth';
+
+export const router = createRouter({
+  history: createWebHistory(),
+  routes: [
+    { path: '/login', name: 'login', component: () => import('../views/LoginView.vue') },
+    { path: '/', name: 'sessions', component: () => import('../views/SessionsListView.vue') },
+    { path: '/sessions/:id', name: 'session', component: () => import('../views/SessionView.vue') },
+    { path: '/:pathMatch(.*)*', redirect: '/' },
+  ],
+});
+
+// Garde globale : tout sauf /login exige une session valide (GET /api/v1/auth/me, 401 → /login)
+router.beforeEach(async (to) => {
+  const auth = useAuthStore();
+  if (auth.authenticated === null) await auth.check();
+  if (to.name === 'login') return auth.authenticated ? { name: 'sessions' } : true;
+  return auth.authenticated ? true : { name: 'login', query: { redirect: to.fullPath } };
+});