FE Tabbed fitness/meal plan view + integration

[kennyjhcheng]

In this PR:

• Created tabbed view of WorkoutSchedule and MealSchedule
  • includes loading backdrop when requests being made
• Created combined reducer for WorkoutAndMealSchedule
• Created MOCK routes in mock.js and associated mock controllers, uses mock data instead of making openAI call
  • to focus on integration and not waste tokens
  • using single endpoint wrapping creation of both workout and meal schedule returning response in format specific by @d-x-s
  • MOCKcreateWorkoutAndMealSchedule controller function

https://github.com/d-x-s/airon-fitness/assets/67628346/44e0425b-65e4-4025-9daf-f5fb9afde183