build: optimize eslint setup

[alexplischke]

1. Change order of eslint extensions. This is very important as the last one in the list (bottom) gets to override conflicting rules of extensions that came before that. Since prettier is our enforcer here, it needs to be at the bottom, not top.
2. The IDE now properly recognizes prettier rules and can yell at you.
3. Use plugin:prettier/recommended instead of prettier, as it configures the entire setup correctly.