feat: Phase 1 — Projektstruktur, DB-Schema, Auth-System

- Vollständige Verzeichnisstruktur gemäß CLAUDE.md
- Express-Server mit Helmet, Sessions, Rate Limiting, SPA-Fallback
- SQLite-Schema (Migration v1): 10 Tabellen, updated_at-Triggers, Indizes
- Versioniertes Migrations-System (schema_migrations)
- Auth-Routen: Login, Logout, /me, Admin-User-CRUD
- Frontend App-Shell: SPA-Router, API-Client, Design-System (CSS Tokens)
- PWA: Service Worker, Web App Manifest
- Setup-Script für ersten Admin-User (node setup.js)
- DB-Tests mit node:sqlite built-in: 29/29 bestanden
- Docker Compose + Dockerfile + Nginx-Beispielkonfiguration

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

public/styles/reset.css

@@ -0,0 +1,83 @@
+/**
+ * Modul: CSS Reset
+ * Zweck: Browser-Defaults normalisieren, Box-Sizing, Touch-Verhalten
+ * Abhängigkeiten: tokens.css
+ */
+
+*, *::before, *::after {
+  box-sizing: border-box;
+  margin: 0;
+  padding: 0;
+}
+
+html {
+  font-family: var(--font-sans);
+  font-size: 16px;
+  line-height: var(--line-height-base);
+  color: var(--color-text-primary);
+  background-color: var(--color-bg);
+  -webkit-text-size-adjust: 100%;
+  -webkit-tap-highlight-color: transparent;
+  scroll-behavior: smooth;
+}
+
+body {
+  min-height: 100dvh;
+  overflow-x: hidden;
+}
+
+img, svg, video {
+  display: block;
+  max-width: 100%;
+}
+
+button {
+  font: inherit;
+  cursor: pointer;
+  border: none;
+  background: none;
+}
+
+input, textarea, select {
+  font: inherit;
+  color: inherit;
+}
+
+a {
+  color: inherit;
+  text-decoration: none;
+}
+
+ul, ol {
+  list-style: none;
+}
+
+h1, h2, h3, h4, h5, h6 {
+  font-weight: var(--font-weight-semibold);
+  line-height: var(--line-height-tight);
+}
+
+/* Touch-Targets: Mindestgröße 44px */
+button, [role="button"], input[type="checkbox"], input[type="radio"] {
+  min-height: 44px;
+}
+
+/* Fokus-Styles (Accessibility) */
+:focus-visible {
+  outline: 2px solid var(--color-accent);
+  outline-offset: 2px;
+  border-radius: var(--radius-xs);
+}
+
+/* Versteckte, aber zugängliche Elemente */
+.sr-only {
+  position: absolute;
+  width: 1px;
+  height: 1px;
+  padding: 0;
+  margin: -1px;
+  overflow: hidden;
+  clip: rect(0, 0, 0, 0);
+  white-space: nowrap;
+  border: 0;
+}