Add Exercise API (FastAPI backend) #2
Description
Idea: Create a simple backend API (using FastAPI) that provides exercises and workouts,
so the timer can be connected to external data instead of hardcoded values.
Example endpoints:
- GET /exercises → return a list of exercises with name and default duration
- GET /workouts → return workout sessions with rounds and rest times
Benefits:
- Makes the timer more flexible
- Allows integration with a future frontend or mobile app
- Good practice for backend + API development