[FR] Building upon ERG mode to enable heart rate zone training

[Sarmyt]

Is your feature request related to a problem? Please describe.
I want to use the SmartSpin2K ERG mode to allow me to stay within limited heart rate zone ranges during my workout.

Describe the solution you'd like
I think the ERG mode on the SmartSpin2K can be leveraged to allow users to stay at a target heartrate during their workout. It would work as follows:

1. User can identify their target heart rate (for example 150 bpm).
2. A PID controller can be used to determine the appropriate watt target that will maintain the target heart rate of the user.
3. ERG mode can be leveraged to stay at the watt target.
4. The watt target will change over time due to the PID controller to allow the user to maintain the target heart rate.

Describe alternatives you've considered
I have not considered any other alternatives.

Additional context
This is a feature I see on many treadmills (treadmills will increase/decrease the speed and incline to allow you to stay at a target heart rate)

[doudar]

With the new Config App and easier data management in and out of the Smartspin2k, this is much easier to implement now