Fix language setting not being saved to database on admin settings page

- Added default_language field to general settings state in SettingsPage
- Replaced LanguageSelector component with simple select dropdown on settings page
- Fixed public settings endpoint to read general_default_language from database
- Language setting now properly saved when clicking Save Settings button
- Setting is correctly used by gallery login page and legal pages

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

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

backend/src/middleware/gallery.js

@@ -0,0 +1,29 @@
+const jwt = require('jsonwebtoken');
+const { db } = require('../database/db');
+
+// Middleware to verify gallery access
+async function verifyGalleryAccess(req, res, next) {
+  try {
+    const token = req.headers.authorization?.split(' ')[1];
+    if (!token) {
+      return res.status(401).json({ error: 'No token provided' });
+    }
+    
+    const decoded = jwt.verify(token, process.env.JWT_SECRET);
+    const event = await db('events').where({ id: decoded.eventId, is_active: true }).first();
+    
+    if (!event) {
+      return res.status(404).json({ error: 'Gallery not found or expired' });
+    }
+    
+    req.event = event;
+    next();
+  } catch (error) {
+    console.error('Error verifying gallery access:', error);
+    res.status(401).json({ error: 'Invalid token', details: error.message });
+  }
+}
+
+module.exports = {
+  verifyGalleryAccess
+};