Refactor/code format

[langdal]

Contribution process clean up

• Update CI pipeline
• Add automatic code formatting (prettier)
• Add API backend to dev container
• Add prettier to pre-commit hook

When this PR has been merged and all other currently open PRs are merged yarn prettier --write . should be run to format all source files. If we do it before merging the other PRs we will have a lot of hard to resolve merge conflicts.