refactor: leverage process.features.typescript instead of node version

[jean-michelet]

Node version is not reliable enough to guess typescript support, but we can leverage process.features.typescript.

fastify/fastify-cli#798 (comment)

[jean-michelet]

I removed nodeVersion from runtime because it is only used here and prevent to reach 100% coverage on the main test suite.

[jean-michelet]

Weird that it didn't fail previously 🤔

[mcollina]

looks great, just one thing.

[mcollina]

lgtm

[bcomnes]

This is a good fix, but leaving a hint here for anyone else coming across this:

In autoloader v6.2.0 or later, autoloader can directly load .ts files, if they are are compatible with native Node.js type stripping, however, if you run the autolodaer in the node-tap test runner with the typescript plugin removed, e.g.

 "tap": {
"plugin": [
      "!@tapjs/typescript"
    ]
}

the autoloader will throw an error about not being able to run typescript directly. To get around this, you can re-enable node-taps typescript plugin and disable typechecking if you don't want it to do anything.

 "tap": {
    "typecheck": false
}

I'm thinking this is something node-tap should fix rather than something addressed here, but in case you come across the same random situation, there is a solution.