Add ElysiaJS option to `fedify init`

[dodok8]

Summary

Add ElysiaJS option to fedify init when user choose bun as runtime.

Problem

Even though there is @fedify/elysia packages, there is no option to make fedify-elysia app at one step.

Proposed Solution

Make Elysia folder under packages/cli/src/init/templates based on examples.

Alternatives Considered

No response

Scope / Dependencies

In next branch, packages/cli/src/init will be affected.