Workout: create routine

[Seerden]

A workout consists of a group of exercises performed in a specific or undefined order.

Request

Would like a minimum viable version of a form component that builds and POSTs a new workout, and a server-side route endpoint that handles insertion of this new workout into the database.

Note

This is a first implementation. A future version of this will contain full-on routine/program functionality, where exercises can be changed out, and sessions planned out in a specific manner (e. g. A/B split with certain exercises being alternated).

[Seerden]

Following up on #8:

• [ ] extend newWorkout validation to also validate exercises. A workout with a name, but with no exercises, is still considered 'valid' currently.
  • should be part of #21