chore: update npm dependencies and node to latest

[backflip]

Updates:

• Update every npm dependency to its latest version
• Remove / replace deprecated packages
• Update Node to 18

Installation is much faster and more stable for me (npm install was often hanging before).

Other optimizations:

• Add lint-staged so we are not linting the whole repo on every commit

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[backflip]

@christophdubach, this is the last "maintenance" PR. With these changes we should have an up-to-date setup.

[backflip]

Successfully tested on Windows, too.