Fix input validation for sets and reps

[ANKITT2006]

Description:

This PR fixes input validation for exercise sets and reps across both the frontend and backend.

Frontend changes:

Improved numeric input controls for sets and reps.
Prevented negative values from being entered.
Improved handling of decimal values and input validation.
Updated the relevant workout configuration components.

Backend/API changes:

Added or improved validation for exercise sets and reps.
Ensured invalid values are handled correctly before being processed or stored.

These changes help maintain consistent validation between the frontend and backend and prevent invalid exercise data from being submitted.

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prototype link :- http://localhost:5173/#/plan/r/mt9k6lvt5zyri

screenshots:-