First draft of worksteps and intermediate products

[sweidlich]

Adds worksteps, finishings and intermediate products.

This will allow to determine which worksteps (including finishings) are required for each job.

Zaikio::MissionControl::Jobs::HardcoverBook.worksteps
=> {:case=>[{:ctp_maybe=>[:plate]}, {:printing=>[:sheet_maybe, :roll_maybe]}, {:cutting_maybe=>[:product]}, {:folding_maybe=>[:fold]}, {:lamination_maybe=>[:laminated_sheet]}],
 :content=>[{:ctp_maybe=>[:plate]}, {:printing=>[:sheet_maybe, :roll_maybe]}, {:cutting=>[:product]}, {:folding=>[:fold]}, {:thread_sewing_maybe=>[:book_block]}, {:lamination_maybe=>[:laminated_sheet]}],
 :endpaper=>[{:ctp_maybe=>[:plate]}, {:printing_maybe=>[:sheet_maybe, :roll_maybe]}, {:cutting_maybe=>[:product]}, {:folding_maybe=>[:fold]}, {:lamination_maybe=>[:laminated_sheet]}],
 :jacket=>[{:ctp_maybe=>[:plate]}, {:printing=>[:sheet_maybe, :roll_maybe]}, {:cutting_maybe=>[:product]}, {:folding_maybe=>[:fold]}, {:lamination_maybe=>[:laminated_sheet]}]}

Part of https://github.com/zaikio/zai-worksteps/issues/57

[YannIsCoding]

Suggested change

	@parts.keys.flat_map do |part|
	parts.flat_map do |part|

[YannIsCoding]

Should we look at adding Zeitwerk at some point? All those requires start to be out of control 🤪