Add boilerplate for iteration cadences form

What does this MR do?

Add controller and view updates to add iteration cadences form.

Depends on iteration_cadences feature flag

Currently just loads empty Vue component

FE for #322741 (closed)

1. This MR
2. Add Vue form - !59227 (merged)
3. ???

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Does this MR meet the acceptance criteria?

Conformity

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