feat: add CommandAckRequest DTO for enriched command acknowledgments

cameleer3-server-app/src/main/java/com/cameleer3/server/app/dto/CommandAckRequest.java

@@ -0,0 +1,10 @@
+package com.cameleer3.server.app.dto;
+
+/**
+ * Request body for command acknowledgment from agents.
+ * Contains the result status and message of the command execution.
+ *
+ * @param status  "SUCCESS" or "FAILURE"
+ * @param message human-readable description of the result
+ */
+public record CommandAckRequest(String status, String message) {}