[BUG] AjvService throws error with `messages: false`
### Describe the bug

When configuring **ajv** by setting `messages: false` in the server configuration the AjvService throws an error, while trying to replace the error message.

### To Reproduce

The related code is:

https://github.com/tsedio/tsed/blob/e660d5b94b7c0978e81055d5536c5bbac9a6c746/packages/specs/ajv/src/services/AjvService.ts#L113

### Expected behavior

The configuration should not break the usage of the AjvService

### Code snippets

_No response_

### Repository URL example

_No response_

### OS

macOs

### Node version

18.17.1

### Library version

7.43.0

### Additional context

_No response_