Feature: E-Mail-Verifikation + Forum öffentlich lesbar + Launch-Vorbereitung

- Forum ohne requiresAuth: öffentlich lesbar, Schreiben weiter via API-Guard
- E-Mail-Verifikation: Token bei Registrierung, support@-Mail, /verify-email/{token}
- Verifikations-Banner (orange, dismissible) wenn email_verified=0
- Grüner Haken / "Nicht bestätigt"-Chip in Settings
- POST /auth/resend-verification für Chip und Banner
- DB-Migration: users.verification_token TEXT
- SW by-v575, APP_VER 552

backend/static/index.html

@@ -108,6 +108,26 @@
         border-radius:999px;padding:1px 7px;font-size:11px;font-weight:700"></span>
 </div>
 
+<!-- E-Mail-Verifikations-Banner -->
+<div id="verify-banner" aria-live="polite"
+     style="display:none;position:fixed;top:0;left:0;right:0;z-index:9998;
+            background:#d97706;color:#fff;font-size:0.8rem;font-weight:500;
+            padding:8px 16px;align-items:center;justify-content:center;gap:10px;
+            box-shadow:0 2px 8px rgba(0,0,0,.2)">
+  <svg xmlns="http://www.w3.org/2000/svg" width="14" height="14" fill="currentColor" viewBox="0 0 256 256">
+    <path d="M224,48H32a8,8,0,0,0-8,8V192a16,16,0,0,0,16,16H216a16,16,0,0,0,16-16V56A8,8,0,0,0,224,48ZM98.71,128,40,181.81V74.19Zm11.84,10.85,12,11.05a8,8,0,0,0,10.82,0l12-11.05,58,53.15H52.57ZM157.29,128,216,74.19V181.81ZM40,61.62l88,80.15,88-80.15Z"/>
+  </svg>
+  <span>Bitte bestätige deine E-Mail-Adresse — wir haben dir eine Mail geschickt.</span>
+  <button id="verify-resend-btn"
+          style="background:rgba(255,255,255,.2);border:none;color:#fff;padding:3px 10px;
+                 border-radius:999px;font-size:0.75rem;cursor:pointer;font-weight:600">
+    Erneut senden
+  </button>
+  <button id="verify-banner-close"
+          style="background:none;border:none;color:#fff;opacity:.7;cursor:pointer;
+                 font-size:1rem;line-height:1;padding:0 4px" aria-label="Schließen">✕</button>
+</div>
+
 <!-- Backdrop + Sidebar direkt im body (kein Ancestor-Stacking-Context) -->
 <div id="sidebar-backdrop" class="sidebar-backdrop"></div>