Volle Mindflux-App ins Deploy-Repo übernehmen

Ersetzt das Hello-World-Gerüst durch die vollständige Anwendung
(com.example.mindflux: 64 Klassen, Thymeleaf-Templates, Static-Assets,
Flyway V1–V6). Deploy-Infrastruktur (.gitea, Dockerfile) bleibt erhalten.

- pom: volle Abhängigkeiten (Security, Thymeleaf, JPA, Flyway), Spring Boot 3.4.4 / Java 17
- docker-compose: SPRING_DATASOURCE_* unverändert; App lauscht auf 8080
  (nginx -> mindflux:8080); Uploads-Volume; Admin-Passwörter via Gitea-Secrets
- Workflow: Deploy-Step injiziert MINDFLUX_ADMIN*_PASSWORD aus Secrets
- .dockerignore ergänzt; Hello-World (com.mindflux) und Test-Datei 'main' entfernt

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/main/resources/templates/admin/dashboard.html

@@ -0,0 +1,83 @@
+<!DOCTYPE html>
+<html lang="de" data-theme="dark"
+      xmlns:th="http://www.thymeleaf.org"
+      xmlns:sec="https://www.thymeleaf.org/thymeleaf-extras-springsecurity6">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>Mindflux Admin Dashboard</title>
+  <link rel="stylesheet" href="/css/theme.css">
+  <script src="/js/theme.js"></script>
+  <style>
+    .admin-actions { display:grid; grid-template-columns:repeat(auto-fit,minmax(240px,1fr)); gap:1rem; margin-top:1.1rem; }
+    .admin-card {
+      display:flex; align-items:center; gap:.6rem;
+      background:var(--surface-2); border:1px solid var(--border-accent); border-radius:13px;
+      padding:1.1rem 1.2rem; color:var(--heading); text-decoration:none; font-weight:700;
+      box-shadow:var(--g-soft); transition:transform .16s ease, box-shadow .25s ease, background-color .2s;
+    }
+    .admin-card:hover { transform:translateY(-3px); background:var(--surface); box-shadow:0 0 18px var(--glow-s); }
+    .admin-footer { margin-top:2rem; text-align:center; color:var(--muted); font-size:.85rem; }
+    .admin-footer a { color:var(--accent); text-decoration:none; }
+    .admin-footer a:hover { text-decoration:underline; }
+  </style>
+</head>
+<body>
+
+<div class="mf-theme-float"><button class="mf-theme"></button></div>
+
+<div class="mf-container">
+
+  <div class="mf-page-head">
+    <a th:href="@{/dashboard}" class="mf-back">⟵ Zurück zum Benutzer-Dashboard</a>
+  </div>
+
+  <header style="margin-bottom:1.4rem">
+    <div class="mf-eyebrow">Control Center</div>
+    <h1 style="color:var(--heading); font-size:1.85rem; font-weight:800; margin-top:.35rem">✨ Admin-Dashboard ✨</h1>
+    <p style="color:var(--muted); margin-top:.4rem">Hier steuerst du das System wie Doc den DeLorean!</p>
+  </header>
+
+  <main>
+
+    <div class="mf-panel accent">
+      <h4>Admin Aktionen</h4>
+      <div class="admin-actions">
+        <a th:href="@{/admin/users}" class="admin-card">👤 Benutzer verwalten</a>
+        <a th:href="@{/admin/mindmatch}" class="admin-card">🧩 MindMatch-Decks verwalten</a>
+        <a th:href="@{/admin/techtacular}" class="admin-card">🎯 TechTacular-Fragen verwalten</a>
+      </div>
+      <p style="margin-top:1.1rem; color:var(--muted);">
+        Hier entsteht noch Großes... ✨ Bleib dran!
+      </p>
+    </div>
+
+  </main>
+
+  <footer class="mf-footer">
+    <a href="#">Support</a>
+    <a href="#">Feedback</a>
+    <a href="#">Nutzungsbedingungen</a>
+    <a href="#">Richtlinien</a>
+    <a href="#">Datenschutz</a>
+    <a href="#">Impressum</a>
+  </footer>
+
+</div>
+
+<script>
+  window.addEventListener('DOMContentLoaded', () => {
+    const successMessage = document.getElementById('successMessage');
+    if (successMessage) {
+      setTimeout(() => {
+        successMessage.style.opacity = '0';
+        setTimeout(() => {
+          successMessage.style.display = 'none';
+        }, 1500);
+      }, 3000);
+    }
+  });
+</script>
+
+</body>
+</html>