feat: WhatsApp Nucleo con Nuxt 4 + Baileys v7

Reemplazo completo de Evolution API por implementación directa con Baileys.

Características:
- Dashboard completo con Nuxt UI v4
- Soporte para múltiples instancias de WhatsApp
- Conexión via QR code o pairing code
- Persistencia de mensajes en PostgreSQL
- API REST para integraciones externas
- Webhooks con firma HMAC
- SSE para actualizaciones en tiempo real
- Autenticación con Authentik

server/api/messages/send.post.ts

@@ -0,0 +1,92 @@
+/**
+ * POST /api/messages/send
+ * Send a message (External API - uses API Key)
+ */
+import { query } from '../../utils/database'
+import { baileysManager } from '../../services/baileys/manager'
+
+interface SendMessageBody {
+  instanceId: string
+  to: string
+  message: string
+}
+
+export default defineEventHandler(async (event) => {
+  // Check API Key authentication
+  const authHeader = getHeader(event, 'authorization')
+
+  if (!authHeader?.startsWith('Bearer ')) {
+    throw createError({ statusCode: 401, message: 'API Key required' })
+  }
+
+  const apiKey = authHeader.slice(7)
+  const config = useRuntimeConfig()
+
+  // Check master API key
+  if (config.masterApiKey && apiKey === config.masterApiKey) {
+    // Master key - allowed
+  } else {
+    // Check database API keys
+    const crypto = await import('crypto')
+    const keyHash = crypto.createHash('sha256').update(apiKey).digest('hex')
+
+    const keyResult = await query(
+      `SELECT id, instance_id FROM api_keys
+       WHERE key_hash = $1 AND is_active = TRUE
+       AND (expires_at IS NULL OR expires_at > NOW())`,
+      [keyHash]
+    )
+
+    if (keyResult.rows.length === 0) {
+      throw createError({ statusCode: 401, message: 'Invalid API Key' })
+    }
+
+    // Update last used
+    await query(
+      'UPDATE api_keys SET last_used_at = NOW() WHERE id = $1',
+      [keyResult.rows[0].id]
+    )
+  }
+
+  // Parse body
+  const body = await readBody<SendMessageBody>(event)
+
+  if (!body.instanceId) {
+    throw createError({ statusCode: 400, message: 'instanceId is required' })
+  }
+  if (!body.to) {
+    throw createError({ statusCode: 400, message: 'to is required' })
+  }
+  if (!body.message?.trim()) {
+    throw createError({ statusCode: 400, message: 'message is required' })
+  }
+
+  // Format JID
+  let jid = body.to.replace(/[^0-9]/g, '')
+  if (!jid.includes('@')) {
+    jid = `${jid}@s.whatsapp.net`
+  }
+
+  // Check instance exists and is connected
+  const status = baileysManager.getStatus(body.instanceId)
+  if (!status || status.status !== 'connected') {
+    throw createError({ statusCode: 400, message: 'Instance not connected' })
+  }
+
+  try {
+    const result = await baileysManager.sendMessage(body.instanceId, jid, {
+      text: body.message
+    })
+
+    return {
+      success: true,
+      messageId: result.key.id,
+      to: jid
+    }
+  } catch (error) {
+    throw createError({
+      statusCode: 500,
+      message: `Failed to send message: ${(error as Error).message}`
+    })
+  }
+})