🔄 fix: Handle Legacy Agent Version Creation (#7718)

* Simplify version creation logic in updateAgent function

* Add comprehensive tests for agent functionality including version history, action metadata generation, and loading agents

- Introduced tests for generating consistent hashes for action metadata.
- Implemented tests for loading agents with various scenarios including null and non-existent IDs.
- Added edge case tests for agent creation, updates, and error handling.
- Ensured proper handling of ephemeral agents and their associated functionalities.

* Enhance tests for Agent model functionality

- Updated test structure for Agent resource file operations, improving organization and readability.
- Added comprehensive tests for handling concurrent file additions and removals, ensuring data integrity.
- Implemented edge case tests for agent creation and resource file management, including scenarios with non-existent agents.
- Enhanced error handling in tests to cover various failure scenarios, ensuring robustness in agent operations.

* optimize tests

api/models/Agent.js

@@ -301,10 +301,7 @@ const updateAgent = async (searchParameter, updateData, options = {}) => {
     }
 
     const shouldCreateVersion =
-      forceVersion ||
-      (versions &&
-        versions.length > 0 &&
-        (Object.keys(directUpdates).length > 0 || $push || $pull || $addToSet));
+      forceVersion || Object.keys(directUpdates).length > 0 || $push || $pull || $addToSet;
 
     if (shouldCreateVersion) {
       const duplicateVersion = isDuplicateVersion(updateData, versionData, versions, actionsHash);