Add server action function name to headers

[amplicity]

Goals

Currently, it's impossible to aggregate next server action information in middleware outside of the next-action header, which specifies the action id. This makes it difficult to conduct server action middleware logging.

The request in middleware exposes next-action as well as the payload, which can be important for debugging. Including a next-action-name could further help debugging and bring logging on par with what we'd expect from traditional restful design patterns.

I understand a log can be added into the function itself. This is great, but it's not as convenient and more error-prone than handling the identification of the function and its params in the middleware.

Non-Goals

No response

Background

This feature is needed to increase the convenience of middleware-based logging. If you design your app to use server actions instead of api endpoints, you lose the ease of consistent logging.

In documentation, it makes it very clear that server actions are meant to be public endpoints. I expect public endpoints to have their route exposed to the public..including the function name aligns with that model.

Proposal

When generating action ids, we should store the function name alongside as well. We should add a header next-action-name that would carry the function name so that it can be used in middleware.