feat: Ergebnis-Banner, Dev-Simulations-Panel & Spiele-Reset

- MatchCard: farbiger Ergebnis-Banner (Exakt/Tendenz/Falsch) ersetzt
  tipRow, passender Card-Glow je Ergebnis; Lucide-Icons (lucide-react)
- MatchCard: Ändern-Button links, vertikal mittig zur Tipp-Box ausgerichtet
- DevPanel: Simulationsmodus mit User-Switcher, Zeit- & Status-Presets
- DevPanel: Reset-Section mit "Spiel zurücksetzen", "Alle Spiele" und
  "Tipps löschen" (3 Buttons, farblich differenziert)
- Backend: dev.ts mit set-time, set-status, reset-tips, reset-match
- reset-match stellt Original-Datum wieder her (original_utc_date Spalte)
- set-time sichert Original-Datum per COALESCE beim ersten Aufruf
- Supabase Migration: original_utc_date TIMESTAMPTZ zu matches hinzugefügt

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/App.tsx

@@ -1,3 +1,4 @@
+import { useState, useEffect } from 'react';
 import { Routes, Route, NavLink } from 'react-router-dom';
 import MatchesPage from './pages/MatchesPage';
 import LeaderboardPage from './pages/LeaderboardPage';
@@ -5,7 +6,47 @@ import ProfilePage from './pages/ProfilePage';
 import AdminPage from './pages/AdminPage';
 import styles from './App.module.css';
 
+const IS_DEV = import.meta.env.DEV;
+
+// Lazy-load DevPanel nur in Development
+let DevPanel: React.ComponentType<any> | null = null;
+if (IS_DEV) {
+  // Dynamic import — kein Bundle-Impact in Production
+  import('./components/DevPanel').then(m => { DevPanel = m.default; });
+}
+
 export default function App() {
+  const [devUser, setDevUser] = useState(1);
+  const [devMatches, setDevMatches] = useState<any[]>([]);
+  const [refreshKey, setRefreshKey] = useState(0);
+
+  // DevUser als Query-Parameter im API-Fetch setzen
+  useEffect(() => {
+    if (!IS_DEV) return;
+    // Patch fetch für Dev-Mode: devUser Query-Param anhängen
+    const origFetch = window.fetch;
+    window._devUser = devUser;
+    window.fetch = (input, init) => {
+      if (typeof input === 'string' && input.startsWith('/api')) {
+        const url = new URL(input, window.location.origin);
+        url.searchParams.set('devUser', String(window._devUser ?? 1));
+        return origFetch(url.toString(), init);
+      }
+      return origFetch(input, init);
+    };
+    return () => { window.fetch = origFetch; };
+  }, [devUser]);
+
+  // Matches für DevPanel laden
+  useEffect(() => {
+    if (!IS_DEV) return;
+    fetch('/api/matches').then(r => r.json()).then(d => setDevMatches(d.matches ?? [])).catch(() => {});
+  }, [refreshKey, devUser]);
+
+  function handleDevRefresh() {
+    setRefreshKey(k => k + 1);
+  }
+
   return (
     <div className={styles.app}>
       <header className={styles.header}>
@@ -13,6 +54,9 @@ export default function App() {
           <div className={styles.logo}>
             <span className={styles.logoFlag}>🏆</span>
             <span className={styles.logoText}>WM 2026 Tippspiel</span>
+            {IS_DEV && (
+              <span className={styles.devBadge}>DEV · User {devUser}</span>
+            )}
           </div>
           <nav className={styles.nav}>
             <NavLink to="/" end className={({ isActive }) => isActive ? styles.navLinkActive : styles.navLink}>
@@ -33,12 +77,21 @@ export default function App() {
 
       <main className={styles.main}>
         <Routes>
-          <Route path="/" element={<MatchesPage />} />
-          <Route path="/rangliste" element={<LeaderboardPage />} />
-          <Route path="/profil" element={<ProfilePage />} />
+          <Route path="/" element={<MatchesPage key={refreshKey} devUser={devUser} />} />
+          <Route path="/rangliste" element={<LeaderboardPage key={refreshKey} />} />
+          <Route path="/profil" element={<ProfilePage key={refreshKey} />} />
           <Route path="/admin" element={<AdminPage />} />
         </Routes>
       </main>
+
+      {IS_DEV && DevPanel && (
+        <DevPanel
+          currentUser={devUser}
+          onUserChange={(u: number) => { setDevUser(u); setRefreshKey(k => k + 1); }}
+          matches={devMatches}
+          onRefresh={handleDevRefresh}
+        />
+      )}
     </div>
   );
 }