Initial commit: PDF OCR Hotfolder v0.1.0

Komplettes Rewrite des alten Bash-Tools `pdf-tool` in Python.
- ocrmypdf als Library, watchdog für Hotfolder, ThreadPool für Parallelität
- Upload-Targets: folder, Nextcloud (WebDAV), SFTP
- E-Mail-Notify, optional veraPDF
- Interaktiver Installer mit Service-User-Support (lokal + AD via SSSD)

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

systemd/pdf-ocr-hotfolder.service

@@ -0,0 +1,25 @@
+[Unit]
+Description=PDF OCR Hotfolder
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+User=__SERVICE_USER__
+Group=__SERVICE_GROUP__
+ExecStart=/opt/pdf-ocr-hotfolder/venv/bin/python -m pdf_ocr_hotfolder --config /etc/pdf-ocr-hotfolder/config.toml
+Restart=on-failure
+RestartSec=5
+KillMode=mixed
+TimeoutStopSec=30
+
+# Hardening (lockerer wegen AD-User & Datei-ACLs)
+NoNewPrivileges=true
+PrivateTmp=true
+ProtectSystem=full
+ProtectKernelTunables=true
+ProtectKernelModules=true
+ProtectControlGroups=true
+
+[Install]
+WantedBy=multi-user.target