feat: MCP Server para control de impresoras

- Endpoint HTTP JSON-RPC en /api/mcp
- 6 tools: list_templates, list_printers, print_template, print_raw, create_template, update_template
- Guia de formato para impresora TM-U220
- Protegido por Authentik forward auth

server/api/mcp/index.post.ts

@@ -0,0 +1,115 @@
+// MCP Server Endpoint - JSON-RPC 2.0 over HTTP
+// Protocolo MCP para agentes de IA
+
+import { MCP_TOOLS, handleToolCall } from '../../utils/mcp'
+
+interface JsonRpcRequest {
+  jsonrpc: '2.0'
+  id: string | number
+  method: string
+  params?: any
+}
+
+interface JsonRpcResponse {
+  jsonrpc: '2.0'
+  id: string | number | null
+  result?: any
+  error?: {
+    code: number
+    message: string
+    data?: any
+  }
+}
+
+export default defineEventHandler(async (event) => {
+  try {
+    const body = await readBody(event) as JsonRpcRequest
+
+    // Validar JSON-RPC
+    if (body.jsonrpc !== '2.0') {
+      return createJsonRpcError(body.id, -32600, 'Invalid Request: jsonrpc must be "2.0"')
+    }
+
+    if (!body.method) {
+      return createJsonRpcError(body.id, -32600, 'Invalid Request: method is required')
+    }
+
+    // Manejar métodos MCP
+    switch (body.method) {
+      case 'initialize': {
+        // Handshake inicial del protocolo MCP
+        return createJsonRpcResponse(body.id, {
+          protocolVersion: '2024-11-05',
+          capabilities: {
+            tools: {}
+          },
+          serverInfo: {
+            name: 'printercentral-mcp',
+            version: '1.0.0'
+          }
+        })
+      }
+
+      case 'initialized': {
+        // Notificación de que el cliente está listo
+        return createJsonRpcResponse(body.id, {})
+      }
+
+      case 'tools/list': {
+        // Listar todas las tools disponibles
+        return createJsonRpcResponse(body.id, {
+          tools: MCP_TOOLS
+        })
+      }
+
+      case 'tools/call': {
+        // Ejecutar una tool
+        const { name, arguments: args } = body.params || {}
+
+        if (!name) {
+          return createJsonRpcError(body.id, -32602, 'Invalid params: tool name is required')
+        }
+
+        // Verificar que la tool existe
+        const tool = MCP_TOOLS.find(t => t.name === name)
+        if (!tool) {
+          return createJsonRpcError(body.id, -32602, `Tool not found: ${name}`)
+        }
+
+        // Ejecutar la tool
+        const result = await handleToolCall(name, args || {})
+        return createJsonRpcResponse(body.id, result)
+      }
+
+      case 'ping': {
+        return createJsonRpcResponse(body.id, {})
+      }
+
+      default:
+        return createJsonRpcError(body.id, -32601, `Method not found: ${body.method}`)
+    }
+  } catch (err: any) {
+    console.error('MCP Error:', err)
+    return createJsonRpcError(null, -32603, `Internal error: ${err.message}`)
+  }
+})
+
+function createJsonRpcResponse(id: string | number | null, result: any): JsonRpcResponse {
+  return {
+    jsonrpc: '2.0',
+    id: id ?? null,
+    result
+  }
+}
+
+function createJsonRpcError(id: string | number | null, code: number, message: string, data?: any): JsonRpcResponse {
+  return {
+    jsonrpc: '2.0',
+    id: id ?? null,
+    error: {
+      code,
+      message,
+      ...(data && { data })
+    }
+  }
+}