docs: update README + Bedienungsanleitung; fix config.py SMTP defaults

- test-alert subcommand documented in both files
- Cron examples extended with www.bergbauspuren-bredelar.de (03:30)
- "Neue Website hinzufügen" updated to URL-first syntax
- Bedienungsanleitung: sitemap option, CF7 ignore_pattern example, generic header
- config.py: SMTP defaults corrected (smtp_host, smtp_user, from, to)

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

scanner/config.py

@@ -58,13 +58,13 @@ DEFAULT_CONFIG: dict = {
         "min_level": "yellow",
         "email": {
             "enabled": False,
-            "smtp_host": "localhost",
+            "smtp_host": "linix.de",
             "smtp_port": 587,
             "smtp_tls": True,
-            "smtp_user": "",
+            "smtp_user": "eliza",
             "smtp_password_env": "SCANNER_SMTP_PASSWORD",
-            "from": "scanner@example.com",
-            "to": [],
+            "from": "eliza@linix.de",
+            "to": ["dieter.schlueter@linix.de"],
         },
         "webhook": {
             "enabled": False,