[Fleet]Restart elastic agents from fleet server remotely

**Describe the enhancement:**
Ability to restart Elastic agents on one or multiple systems from the fleet section through the fleet server
**Describe a specific use case for the enhancement or feature:**

Restarting Elastic Agents from Fleet Server can save time and effort compared to manually restarting each individual agent. This is especially useful when managing a large number of agents across multiple hosts.It allows you to push updated configuration to the agent without having to manually update each individual agent. This can save time and reduce the risk of errors.