feat: Mini-Cloud Plattform - komplette Implementierung Phase 0-8

Selbstgehostete Web-Cloud mit Dateiverwaltung, Kalender, Kontakte,
Email-Webclient, Office-Viewer und Passwort-Manager.

Backend (Flask/Python):
- JWT-Auth mit Access/Refresh Tokens, Benutzerverwaltung
- Dateien: Upload/Download, Ordner, Berechtigungen, Share-Links
- Kalender: CRUD, Teilen, iCal-Export, CalDAV well-known URLs
- Kontakte: Adressbuecher, vCard-Export, Teilen
- Email: IMAP/SMTP-Proxy, Multi-Account
- Office-Viewer: DOCX/XLSX/PPTX/PDF Vorschau
- Passwort-Manager: AES-256-GCM clientseitig, KeePass-Import
- Sync-API fuer Desktop/Mobile-Clients
- SQLite mit WAL-Modus

Frontend (Vue 3 + PrimeVue):
- Datei-Explorer mit Breadcrumbs und Share-Dialogen
- Monatskalender mit Event-Verwaltung
- Kontaktliste mit Adressbuch-Sidebar
- Email-Client mit 3-Spalten-Layout
- Passwort-Manager mit TOTP und Passwort-Generator
- Admin-Panel, Settings, oeffentliche Share-Seite

Docker: Multi-Stage Build, Bind Mounts (keine Volumes)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/app/models/file.py

@@ -0,0 +1,82 @@
+from datetime import datetime, timezone
+
+from app.extensions import db
+
+
+class File(db.Model):
+    __tablename__ = 'files'
+
+    id = db.Column(db.Integer, primary_key=True)
+    owner_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False, index=True)
+    parent_id = db.Column(db.Integer, db.ForeignKey('files.id'), nullable=True, index=True)
+    name = db.Column(db.String(255), nullable=False)
+    is_folder = db.Column(db.Boolean, default=False, nullable=False)
+    mime_type = db.Column(db.String(255), nullable=True)
+    size = db.Column(db.BigInteger, default=0)
+    storage_path = db.Column(db.String(500), nullable=True)  # UUID-based path on disk
+    checksum = db.Column(db.String(64), nullable=True)  # SHA-256 for sync
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(timezone.utc))
+    updated_at = db.Column(db.DateTime, default=lambda: datetime.now(timezone.utc),
+                           onupdate=lambda: datetime.now(timezone.utc))
+
+    # Relationships
+    children = db.relationship('File', backref=db.backref('parent', remote_side='File.id'),
+                               lazy='dynamic')
+    permissions = db.relationship('FilePermission', backref='file', lazy='dynamic',
+                                  cascade='all, delete-orphan')
+    share_links = db.relationship('ShareLink', backref='file', lazy='dynamic',
+                                  cascade='all, delete-orphan')
+
+    def to_dict(self):
+        return {
+            'id': self.id,
+            'owner_id': self.owner_id,
+            'parent_id': self.parent_id,
+            'name': self.name,
+            'is_folder': self.is_folder,
+            'mime_type': self.mime_type,
+            'size': self.size,
+            'created_at': self.created_at.isoformat() if self.created_at else None,
+            'updated_at': self.updated_at.isoformat() if self.updated_at else None,
+        }
+
+
+class FilePermission(db.Model):
+    __tablename__ = 'file_permissions'
+
+    id = db.Column(db.Integer, primary_key=True)
+    file_id = db.Column(db.Integer, db.ForeignKey('files.id'), nullable=False, index=True)
+    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False, index=True)
+    permission = db.Column(db.String(20), nullable=False)  # 'read', 'write', 'admin'
+
+    user = db.relationship('User', backref='file_permissions')
+
+    __table_args__ = (
+        db.UniqueConstraint('file_id', 'user_id', name='uq_file_user_permission'),
+    )
+
+
+class ShareLink(db.Model):
+    __tablename__ = 'share_links'
+
+    id = db.Column(db.Integer, primary_key=True)
+    file_id = db.Column(db.Integer, db.ForeignKey('files.id'), nullable=False, index=True)
+    token = db.Column(db.String(64), unique=True, nullable=False, index=True)
+    password_hash = db.Column(db.String(255), nullable=True)
+    expires_at = db.Column(db.DateTime, nullable=True)
+    created_by = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False)
+    download_count = db.Column(db.Integer, default=0)
+    max_downloads = db.Column(db.Integer, nullable=True)
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(timezone.utc))
+
+    creator = db.relationship('User', backref='share_links')
+
+    def is_expired(self):
+        if self.expires_at is None:
+            return False
+        return datetime.now(timezone.utc) > self.expires_at
+
+    def is_download_limit_reached(self):
+        if self.max_downloads is None:
+            return False
+        return self.download_count >= self.max_downloads