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 <[email protected]>

backend/migrations/run-migrations.js

@@ -0,0 +1,91 @@
+const fs = require('fs').promises;
+const path = require('path');
+const { db } = require('../src/database/db');
+
+// Create migrations table if it doesn't exist
+async function createMigrationsTable() {
+  const tableExists = await db.schema.hasTable('migrations');
+  if (!tableExists) {
+    await db.schema.createTable('migrations', (table) => {
+      table.increments('id').primary();
+      table.string('filename').unique().notNullable();
+      table.timestamp('applied_at').defaultTo(db.fn.now());
+    });
+    console.log('Created migrations table');
+  }
+}
+
+// Get list of applied migrations
+async function getAppliedMigrations() {
+  const migrations = await db('migrations').select('filename');
+  return migrations.map(m => m.filename);
+}
+
+// Run a single migration
+async function runMigration(filename) {
+  const migrationPath = path.join(__dirname, filename);
+  const migration = require(migrationPath);
+  
+  if (migration.up) {
+    console.log(`Running migration: ${filename}`);
+    await migration.up();
+    await db('migrations').insert({ filename });
+    console.log(`Migration ${filename} completed`);
+  }
+}
+
+// Main migration runner
+async function runMigrations() {
+  try {
+    console.log('Starting database migrations...');
+    
+    // First run the init.js if it exists
+    const initPath = path.join(__dirname, 'init.js');
+    if (require.resolve(initPath)) {
+      console.log('Running initial setup...');
+      require(initPath);
+      // Wait a bit for init to complete
+      await new Promise(resolve => setTimeout(resolve, 2000));
+    }
+    
+    // Create migrations table
+    await createMigrationsTable();
+    
+    // Get all migration files
+    const files = await fs.readdir(__dirname);
+    const migrationFiles = files
+      .filter(f => f.match(/^\d{3}_.*\.js$/))
+      .sort();
+    
+    // Get applied migrations
+    const appliedMigrations = await getAppliedMigrations();
+    
+    // Run pending migrations
+    let pendingCount = 0;
+    for (const file of migrationFiles) {
+      if (!appliedMigrations.includes(file)) {
+        await runMigration(file);
+        pendingCount++;
+      }
+    }
+    
+    if (pendingCount === 0) {
+      console.log('No pending migrations');
+    } else {
+      console.log(`Applied ${pendingCount} migration(s)`);
+    }
+    
+    console.log('All migrations completed successfully');
+    process.exit(0);
+  } catch (error) {
+    console.error('Migration failed:', error);
+    process.exit(1);
+  }
+}
+
+// Only run if called directly
+if (require.main === module) {
+  runMigrations();
+}
+
+module.exports = { runMigrations };