fix: implement 9 production enhancements and security fixes

- Password Complexity: Added 4-level complexity selector (Simple/Moderate/Strong/Very Strong) in admin security settings with dynamic backend validation
- Gallery Security: Removed event date from login page (security risk), replaced with event type badge
- Analytics Config: Fixed "Not Configured" detection logic to check both admin settings and env variables
- Analytics Accuracy: Aligned calculation logic between dashboard and analytics endpoints, added totals verification
- Translations: Added missing activity keys (analytics_settings_updated, cms_page_updated, security_settings_updated, password_reset, admin_logout, system_activity)
- UI Fixes: Fixed German text overflow in CMS page selector with proper CSS truncation
- Date Format: Event creation now respects admin-configured date format instead of browser locale
- Chrome Compatibility: Replaced emoji flags with SVG components for Windows Chrome support

All changes maintain backward compatibility and production stability.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

frontend/src/components/common/LanguageSelector.tsx

@@ -2,9 +2,28 @@ import React from 'react';
 import { useTranslation } from 'react-i18next';
 import { Globe } from 'lucide-react';
 
+// SVG Flag Components
+const GBFlag: React.FC<{ className?: string }> = ({ className = "w-5 h-5" }) => (
+  <svg className={className} viewBox="0 0 640 480" xmlns="http://www.w3.org/2000/svg">
+    <path fill="#012169" d="M0 0h640v480H0z"/>
+    <path fill="#FFF" d="m75 0 244 181L562 0h78v62L400 241l240 178v61h-80L320 301 81 480H0v-60l239-178L0 64V0h75z"/>
+    <path fill="#C8102E" d="m424 281 216 159v40L369 281h55zm-184 20 6 35L54 480H0l240-179zM640 0v3L391 191l2-44L590 0h50zM0 0l239 176h-60L0 42V0z"/>
+    <path fill="#FFF" d="M241 0v480h160V0H241zM0 160v160h640V160H0z"/>
+    <path fill="#C8102E" d="M0 193v96h640v-96H0zM273 0v480h96V0h-96z"/>
+  </svg>
+);
+
+const DEFlag: React.FC<{ className?: string }> = ({ className = "w-5 h-5" }) => (
+  <svg className={className} viewBox="0 0 640 480" xmlns="http://www.w3.org/2000/svg">
+    <path fill="#000" d="M0 0h640v160H0z"/>
+    <path fill="#D00" d="M0 160h640v160H0z"/>
+    <path fill="#FFCE00" d="M0 320h640v160H0z"/>
+  </svg>
+);
+
 const languages = [
-  { code: 'en', name: 'English', flag: '🇬🇧' },
-  { code: 'de', name: 'Deutsch', flag: '🇩🇪' },
+  { code: 'en', name: 'English', Flag: GBFlag },
+  { code: 'de', name: 'Deutsch', Flag: DEFlag },
 ];
 
 export const LanguageSelector: React.FC = () => {
@@ -25,7 +44,7 @@ export const LanguageSelector: React.FC = () => {
         className="flex items-center gap-2 px-3 py-2 text-sm font-medium text-neutral-700 bg-white border border-neutral-300 rounded-lg hover:bg-neutral-50 focus:outline-none focus:ring-2 focus:ring-primary-500"
       >
         <Globe className="w-4 h-4" />
-        <span>{currentLanguage.flag}</span>
+        <currentLanguage.Flag className="w-5 h-5" />
         <span>{currentLanguage.name}</span>
       </button>
 
@@ -41,7 +60,7 @@ export const LanguageSelector: React.FC = () => {
                   : 'text-neutral-700'
               }`}
             >
-              <span className="text-lg">{language.flag}</span>
+              <language.Flag className="w-5 h-5" />
               <span>{language.name}</span>
             </button>
           ))}