[Feature Request] Add eye and face calibration option to UI

I am currently developing the VRCFT v5 Pimax Module, and as part of the module's usage users need to calibrate their eye tracking. This was historically done by either entering a character on a keyboard, or toggling a parameter on their avatar `CalibrateEyeTracking` and `CalibrateFaceTracking`.

# Proposition
This is a draft, feedback is welcome.

## UI Integration

I believe the calibration button(s) should go here, to the left of "Toggle Tracking"


## Module Integration

For module developers to opt into calibration, they can define a function that can be called when said button(s) are pressed. This is similar to how to `Update` function already works. This (should) need(s) a place in OSCMain, ExtTrackingModule, and the respective module loaders.

`OSCMain`


## Remark - OSC Integration

So this system is compatible with VRChat, I propose the `"/avatar/parameters/CalibrateEyeTracking"` and `"/avatar/parameters/CalibrateFaceTracking"` be added to `OSCMain`'s switch function, next to the `/avatar/change` block.