refactor(edit-name-agent-modal): add isValid flag for name validation

This change introduces an `isValid` flag to the validation state, improving clarity and consistency when checking if the agent name is valid. The flag is used in the Enter key handler to determine if the save action should proceed.

Author: yenienserrano

plugins/wazuh-fleet/public/components/agents/list/actions/edit-name-agent-modal.tsx

@@ -33,9 +33,11 @@ export const EditAgentNameModal = ({
   const [newName, setNewName] = useState('');
   const [isSaving, setIsSaving] = useState(false);
   const [validateName, setValidateName] = useState<{
+    isValid: boolean;
     isInvalid: boolean;
     errors: string[];
   }>({
+    isValid: true,
     isInvalid: false,
     errors: [],
   });
@@ -61,6 +63,7 @@ export const EditAgentNameModal = ({
     }
 
     setValidateName({
+      isValid: errors.length === 0,
       isInvalid: errors.length > 0,
       errors: errors,
     });
@@ -118,7 +121,7 @@ export const EditAgentNameModal = ({
                 if (event.key === 'Enter') {
                   event.preventDefault();
 
-                  if (!validateName.isInvalid) {
+                  if (validateName.isValid) {
                     handleSave();
                   }
                 }