Time-based Cover with tilt function

**Describe the problem you have/What new integration you would like**
I have tilting venetian exterior blinds, it is the kind with one motor, has built in endstops. When they move up, they first tilt open, then start moving up, when they move down, they first tilt close, then start moving down. It would be nice to be able to set not only open_duration and close_duration, but also tilt_close_duration and tilt_open_duration. In my case this is around 0.9sec. This time is included in the total close/open time, since when they are fully open, they first need close before moving down, and vice versa, when they are fully down, when moving up, they first need to open, then they start moving.

**Example**
- close_duration set to 60sec
- tilt_open/close_duration set to 1sec
- I command to blind to close to 50%
- Blind starts moving down, counts to 30sec, then stops. 30s is saved as current position
- I set the tilt to open, motor starts moving the blind up for 1sec, but also subtracting the position from 30sec, so now only 29sec left for the position.

The tilt could really be stateless, either close or open, perhaps also 45deg.
I know there is a problem with synchronizing the states of tilt, because it would have to set the tilt state to closed when the blind was previously moving down, and set the tilt state to open if the blind was previously moving up for longer than tilt_open/close_duration, so the tilt could be stateless and it would just run the motor down for 1sec to close then, in worst case it would move the blind down slightly if it the tilt was previously closed, but counting this to the overall position time, so it wouldn't lose the track of position.

**Please describe your use case for this integration and alternatives you've tried:**
For tilting blinds with single motor with up/down direction.
I have tried setting up internal time_based cover, just to keep track of the position based on time, then setting up template cover, manually counting the time for the tilt, and this template cover was controlling the internal time based cover, this sorta worked, but is a bit clumsy.

**Additional context**
The blind uses Somfy WT motor, which has internal position tracking and has endpoints set.
Thank you