Initial commit: Simple Notes Sync project setup

Features:
- Docker WebDAV server with docker-compose
- Server configuration with .env
- Project structure for Android app
- Complete documentation references
- MIT License

Server:
- bytemark/webdav Docker image
- Basic authentication
- Port 8080 exposed
- Volume mounts for data and logs
- Quick start README

Android:
- Project structure defined
- README with setup instructions
- Links to complete implementation guide

Status: Server running and tested ✓
Next: Android app implementation in Android Studio

server/README.md

@@ -0,0 +1,63 @@
+# WebDAV Server - Simple Notes Sync
+
+## Quick Start
+
+```bash
+# 1. Umgebungsvariablen anpassen
+cp .env.example .env
+nano .env
+
+# 2. Server starten
+docker-compose up -d
+
+# 3. Logs prüfen
+docker-compose logs -f
+
+# 4. Testen
+curl -u noteuser:your_password http://localhost:8080/
+```
+
+## Server URL
+
+**Lokal:** `http://localhost:8080/`
+
+**Im Netzwerk:** `http://YOUR_IP:8080/` (z.B. `http://192.168.1.100:8080/`)
+
+IP-Adresse herausfinden:
+```bash
+ip addr show | grep "inet " | grep -v 127.0.0.1
+```
+
+## Credentials
+
+Standard (siehe `.env`):
+- Username: `noteuser`
+- Password: Siehe `.env` Datei
+
+## Management
+
+```bash
+# Status prüfen
+docker-compose ps
+
+# Logs anschauen
+docker-compose logs -f
+
+# Neustarten
+docker-compose restart
+
+# Stoppen
+docker-compose down
+
+# Komplett löschen (inkl. Daten)
+docker-compose down -v
+```
+
+## Daten
+
+Notizen werden gespeichert in: `./notes-data/`
+
+Backup erstellen:
+```bash
+tar -czf backup-$(date +%Y%m%d).tar.gz notes-data/
+```