Add option to ignore SSL/TLS certificate errors for email (Issue #53)

This feature allows users with non-standard SMTP setups (shared hosting,
self-signed certificates) to bypass certificate validation when needed.

Changes:
- Add database migration for tls_reject_unauthorized column
- Update emailProcessor.js to pass TLS option to nodemailer
- Update adminEmail.js routes to handle the new field
- Add checkbox UI with security warning in EmailConfigPage
- Add English and German translations

frontend/src/i18n/locales/en.json

@@ -1072,7 +1072,9 @@
     "enterPassword": "Enter password",
     "fromEmail": "From Email",
     "fromName": "From Name",
-    "required": "required"
+    "required": "required",
+    "ignoreSslErrors": "Ignore SSL/TLS certificate errors",
+    "ignoreSslWarning": "Warning: Disabling certificate verification makes the connection vulnerable to man-in-the-middle attacks. Only enable this if you trust the SMTP server and understand the security implications."
   },
   "cms": {
     "title": "CMS Pages",