Add JsonOutput import to fix MCP servlet functionality

- Fixed missing JsonOutput import in EnhancedMcpServlet.groovy
- Resolves 'No such property: JsonOutput' error
- MCP server now properly handles JSON responses
- Size protection and screen execution working correctly

@@ -16,6 +16,7 @@ package org.moqui.mcp
 import groovy.json.JsonSlurper
 import org.moqui.impl.context.ExecutionContextFactoryImpl
 import groovy.json.JsonBuilder
+import groovy.json.JsonOutput
 import org.moqui.context.ArtifactAuthorizationException
 import org.moqui.context.ArtifactTarpitException
 import org.moqui.impl.context.ExecutionContextImpl