fix: allow date formats as gallery passwords

- Modified backend password validation for galleries to be more lenient
- Reduced minimum password length to 6 characters for galleries
- Removed uppercase/lowercase/number requirements for gallery passwords
- Allow date formats like "04.07.2025" as passwords
- Added helper text to inform users about password options
- Still prevent overly simple passwords like "123456"
- Admin passwords remain strict with all security requirements

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

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

frontend/src/pages/admin/CreateEventPage.tsx

@@ -204,6 +204,9 @@ export const CreateEventPage: React.FC = () => {
       newErrors.password = t('validation.passwordRequired');
     } else if (formData.password.length < 6) {
       newErrors.password = t('validation.passwordMinLength');
+    } else if (/^\d{1,6}$/.test(formData.password)) {
+      // Prevent simple numeric passwords like "123456"
+      newErrors.password = t('validation.passwordTooSimple', 'Password cannot be just numbers. Consider using a date format like "04.07.2025"');
     }
 
     if (formData.password !== formData.confirm_password) {
@@ -412,6 +415,7 @@ export const CreateEventPage: React.FC = () => {
                   onChange={handleInputChange('password')}
                   error={errors.password}
                   placeholder={t('events.enterPassword')}
+                  helperText={t('events.passwordHelperText', 'You can use dates like "04.07.2025" or any text with 6+ characters')}
                   leftIcon={<Lock className="w-5 h-5 text-neutral-400" />}
                   className="pr-10"
                 />

frontend/src/pages/admin/CreateEventPageEnhanced.tsx

@@ -180,6 +180,9 @@ export const CreateEventPageEnhanced: React.FC = () => {
       newErrors.password = t('validation.passwordRequired');
     } else if (formData.password.length < 6) {
       newErrors.password = t('validation.passwordMinLength');
+    } else if (/^\d{1,6}$/.test(formData.password)) {
+      // Prevent simple numeric passwords like "123456"
+      newErrors.password = t('validation.passwordTooSimple', 'Password cannot be just numbers. Consider using a date format like "04.07.2025"');
     }
 
     if (formData.password !== formData.confirm_password) {
@@ -453,6 +456,7 @@ export const CreateEventPageEnhanced: React.FC = () => {
                 value={formData.password}
                 onChange={handleInputChange('password')}
                 error={errors.password}
+                helperText={t('events.passwordHelperText', 'You can use dates like "04.07.2025" or any text with 6+ characters')}
                 leftIcon={<Lock className="w-5 h-5" />}
                 rightIcon={
                   <button