could you add support of svelte?

[superiums]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the feature has not already been requested

🚀 Feature Proposal

could you add support of svelte? or a custom engine support ?

Motivation

simiar with https://www.liip.ch/en/blog/mvc-with-nestjs-and-svelte

Example

export interface FastifyViewOptions {
    engine: {
        ejs?: any;
        ......

        svelted?: any;
    };

[mcollina]

I think we should have a different plugin for Svelte integration. Maybe this is something @galvez could help with.