[FEATURE REQUEST] Report time until next filament change in GET /api/v1/status

[nomike]

This endpoint currently reports (amongst other things):

{
  "job": {
    "id": 420,
    "progress": 42,
    "time_remaining": 520,
    "time_printing": 526
  },
...

A field time_change (or similarly named) should be added. which shows the time until the next filament change, print pause or other planned user interaction.

This would allow better integration in Home Assistant for example, allowing notifications being sent before user interaction is required, much like the new Prusa Android app is doing.