Build interactive prototype for UAT

Develop an interactive prototype to validate user journeys and functional requirements during user acceptance testing.

**Story Points:** 3

Start by reviewing the user journeys and functional requirements that the prototype must validate during user acceptance testing. Define the prototype scope around those journeys and requirements, then confirm it supports the intended UAT validation; the issue does not name files, tests, or an entry point.

Written by the indexing model from the issue text.