Switch to HTTP APIs by default

[mnapoli]

The goal is to move towards HTTP APIs instead of REST APIs, at least for the most common scenarios.

This PR updates some examples, and duplicates some other examples. More specifically, it:

• introduces new examples focused on HTTP APIs (they duplicate existing "rest-api" examples, in order to preserve examples about REST APIs)
• update existing examples that were not focused on REST APIs

The goal was to keep examples about REST (not remove them entirely).

Some examples, like "expressjs", "simple HTTP endpoint", etc. were not specifically about REST APIs, so I updated them to use HTTP APIs.

TODO:

• JS
• Typescript
• Python
• Ruby
• Go
• Java
• Rust
• Update the documentation to use HTTP APIs by default: docs: Switch to HTTP APIs by default serverless#9777

[pgrzesik]

Looks good in general, good call 👍 I have only one concern, other than that we should be good to go here

[pgrzesik]

good call 👍

[mnapoli]

👍 some templates had this, some others didn't. I figured we might as well make it consistent over this option, it's best to get started.

[mnapoli]

This PR is ready.

After merging this, the next step will be serverless/serverless#9777 (and what's in TODO in that PR). This PR here can be merged and that will unblock the other tasks (@pgrzesik let me know if I'm wrong and we need to merge something simultaneously, but I don't think this is the case, I think we can merge this now and do serverless/serverless#9777 afterwards).

[pgrzesik]

Thanks @mnapoli - in general we should always merge changes here first if we're adding new examples. If we're modifying existing ones, then the onboarding will use them right after they are merge here. It's going to be the case e.g. for aws-node-express-api from your changes. Are you okay that from now on, even in previous versions, that example will use HTTP API instead of REST API?