feat(guide): Testing role-tab (fleet pilot) + sidebar identity indicator

- New Testing tab (order 35, audience internal, 🧪): test accounts, manual flow,
  copy-paste API smoke tests, role/scoping checks, regression watch. Fleet pilot.
- Reader shows 'Signed in as {email} · {role}' above Sign out (decoded from JWT),
  so you always know which identity you're testing as.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/App.svelte

@@ -11,6 +11,14 @@
   let showPassword = false;
   let loginError = '';
   let loggingIn = false;
+  let userInfo: { email: string; role: string } | null = null;
+
+  function decodeJwt(t: string): { email: string; role: string } | null {
+    try {
+      const p = JSON.parse(atob(t.split('.')[1].replace(/-/g, '+').replace(/_/g, '/')));
+      return { email: p.email ?? '', role: p.role ?? '' };
+    } catch { return null; }
+  }
 
   async function checkAuth() {
     const t = getToken();
@@ -18,6 +26,7 @@
     try {
       await authApi.get('/api/users/me', { headers: { Authorization: `Bearer ${t}` } });
       authenticated = true;
+      userInfo = decodeJwt(t);
     } catch {
       clearToken();
     } finally {
@@ -33,6 +42,7 @@
       const token = res.data.token;
       if (!token) throw new Error('No token in response');
       setToken(token);
+      userInfo = decodeJwt(token);
       authenticated = true;
     } catch (e: any) {
       loginError = e?.response?.data?.message ?? 'Invalid email or password.';
@@ -41,7 +51,7 @@
     }
   }
 
-  function logout() { clearToken(); authenticated = false; }
+  function logout() { clearToken(); authenticated = false; userInfo = null; }
 
   onMount(checkAuth);
 </script>
@@ -80,7 +90,7 @@
     </div>
   </div>
 {:else}
-  <GuideReader on:logout={logout} />
+  <GuideReader on:logout={logout} userEmail={userInfo?.email ?? ''} userRole={userInfo?.role ?? ''} />
 {/if}
 
 <!-- Toast notifications -->

frontend/src/components/GuideReader.svelte

@@ -6,6 +6,8 @@
   import { addToast } from '../lib/stores';
 
   const dispatch = createEventDispatcher();
+  export let userEmail = '';
+  export let userRole = '';
 
   let nav: NavApp[] = [];
   let loadingNav = true;
@@ -33,7 +35,7 @@
 
   // role-tab icons (Customer / Internal / Architect / Claude)
   const ROLE_ICON: Record<string, string> = {
-    Customer: '👤', Internal: '🔧', Architect: '📐', Claude: '✨', Overview: '📄', Data: '🗄️', Technical: '📐',
+    Customer: '👤', Internal: '🔧', Architect: '📐', Testing: '🧪', Claude: '✨', Overview: '📄', Data: '🗄️', Technical: '📐',
   };
 
   $: filtered = !search.trim()
@@ -161,6 +163,13 @@
       {/if}
     </nav>
 
+    {#if userEmail}
+      <div class="side-user">
+        <span class="side-user-label">Signed in as</span>
+        <span class="side-user-email" title={userEmail}>{userEmail}</span>
+        {#if userRole}<span class="side-user-role">{userRole}</span>{/if}
+      </div>
+    {/if}
     <button class="side-logout" on:click={() => dispatch('logout')}>Sign out</button>
   </aside>
 
@@ -258,6 +267,19 @@
   .nav-item:hover { background: rgba(255,255,255,0.08); color: white; }
   .nav-item.active { background: rgba(255,255,255,0.14); color: white; border-left-color: white; font-weight: 600; }
 
+  .side-user {
+    margin: 0.4rem 1rem 0.2rem; padding: 0.5rem 0.15rem 0.4rem;
+    border-top: 1px solid rgba(255,255,255,0.12);
+    display: flex; flex-direction: column; gap: 1px;
+  }
+  .side-user-label { color: rgba(255,255,255,0.5); font-size: 0.62rem; text-transform: uppercase; letter-spacing: 0.05em; }
+  .side-user-email { color: rgba(255,255,255,0.92); font-size: 0.78rem; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
+  .side-user-role {
+    align-self: flex-start; margin-top: 3px;
+    color: #93c5fd; background: rgba(59,130,246,0.18); border: 1px solid rgba(59,130,246,0.35);
+    font-size: 0.6rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em;
+    border-radius: 4px; padding: 1px 6px;
+  }
   .side-logout {
     margin: 0.5rem 1rem 1rem; padding: 0.5rem; border-radius: 6px;
     background: rgba(255,255,255,0.1); border: 1px solid rgba(255,255,255,0.2);