feat(blogpost): Type-safe webpack/jest/prettier config with TypeScript without using it at all

[Hotell]

• why types are useful/needed beyond application logic ( for our dev-stack tooling configuration )
• what did we use till now ( ts-node, tsc && node ... )
• showcase by using JSDoc and @ts-check to write simple Webpack config
  • hoisting all types on top of file
  • extracting types to separate files ( pattern )
  • defining ambient types for 3rd party libraries that don't have types ( pattern )
• typing jest and prettier config
• validation npm-script