feat: implement real tenant creation and listing

backend/index.js

@@ -123,13 +123,56 @@ app.get('/api/attendances/:id', async (req, res) => {
 // --- Rotas de Tenants (Super Admin) ---
 app.get('/api/tenants', async (req, res) => {
   try {
-    const [rows] = await pool.query('SELECT * FROM tenants');
+    // Buscar tenants e contar usuários/atendimentos
+    const query = `
+      SELECT t.*, 
+        (SELECT COUNT(*) FROM users u WHERE u.tenant_id = t.id) as user_count,
+        (SELECT COUNT(*) FROM attendances a WHERE a.tenant_id = t.id) as attendance_count
+      FROM tenants t
+    `;
+    const [rows] = await pool.query(query);
     res.json(rows);
   } catch (error) {
     res.status(500).json({ error: error.message });
   }
 });
 
+// Criar Tenant
+app.post('/api/tenants', async (req, res) => {
+  const { name, slug, admin_email, status } = req.body;
+  const crypto = require('crypto');
+  
+  const connection = await pool.getConnection();
+  try {
+    await connection.beginTransaction();
+
+    const tenantId = `tenant_${crypto.randomUUID().split('-')[0]}`; // Simple ID generation
+    
+    // 1. Criar Tenant
+    await connection.query(
+      'INSERT INTO tenants (id, name, slug, admin_email, status) VALUES (?, ?, ?, ?, ?)',
+      [tenantId, name, slug, admin_email, status || 'active']
+    );
+
+    // 2. Criar Usuário Admin Default
+    const userId = `u_${crypto.randomUUID().split('-')[0]}`;
+    await connection.query(
+      'INSERT INTO users (id, tenant_id, name, email, role, status) VALUES (?, ?, ?, ?, ?, ?)',
+      [userId, tenantId, 'Admin', admin_email, 'admin', 'active']
+    );
+
+    await connection.commit();
+    res.status(201).json({ message: 'Tenant created successfully', id: tenantId });
+  } catch (error) {
+    await connection.rollback();
+    console.error('Erro ao criar tenant:', error);
+    res.status(500).json({ error: error.message });
+  } finally {
+    connection.release();
+  }
+});
+
+
 // Serve index.html for any unknown routes (for client-side routing)
 if (process.env.NODE_ENV === 'production') {
   app.get('*', (req, res) => {