[usage] Initial setup for component

[easyCZ]

Description

Initial setup for usage-component. This component will be responsible for collecting usage data and eventually creating invoices for SaaS.

This is based on RFC: Usage based pricing (internal)

Related Issue(s)

Fixes #

How to test

#10227 (comment)

Release Notes

NONE

Documentation

NONE

[jankeromnes]

Many thanks @easyCZ!

Could you please add a few hints to the How to test section? (FYI I tried opening your PR in Gitpod, and looked for a usage-xyz pod running, but there was none)

[easyCZ]

@jankeromnes there's currently nothing to test really. It's not yet deployed anywhere as this PR only performs component setup.

One test you can run is cd components/usage && go run main.go to check it runs. This is in a way already tested through CI as we build the component with werft

[easyCZ]

I've changed the hello world in this PR to use baseserver and start it. This then runs the metrics and live/ready endpoints os we can better test this.

To run the test, do

cd components/usage

go run main.go run

and in another terminal, run curl localhost:9502/metrics which demonstrates the server running and serving metrics.

[jankeromnes]

Many thanks @easyCZ! 👍

Briefly skimmed the code, looks good, ran the provided test commands, works, and generally Gitpod still seems to work fine. 🎉