[feat]: Use StartOS SMTP Server

### Prerequisites

- [X] I have searched for existing issues that already suggest this feature.

### Describe the Feature Request

Ability to send emails from Embassy for notifications, user registration, password resets, etc

### Describe the Use Case

self-explanatory

### Describe Preferred Solution

_No response_

### Describe Alternatives

_No response_

### Anything else?

_No response_