[Feature Request] Rework priority handling

RFC 5545 specifies 1-4 as High, 5 as Medium and 6-9 as high with 0 as "Undefined/No priority".

Most task managers, including all I've been able to sync with NC Tasks uses a four-level system; No Priority-Low-Medium-High instead of the full 10 levels defined in RFC 5545. This corresponds with NC Tasks own four colour scheme - Grey (No priority), Blue (Low priority), Yellow (Medium priority) and Red (High priority). The 10-level slider in Tasks is confusing when compared to it's own colour scheme and other task managers.

I request that the priorities slider is either changed to the defacto standard, RFC 5545-compliant four-levels; No priority Grey=0, High priority Red=1, Medium priority Yellow=5 and Low priority Blue=9 - Or have the option to toggle this feature akin to Calendars "Simplified Editor".

Thank you for your consideration and providing a great NC feature!

No file or test is named. Start by locating the existing priority slider and its RFC 5545 mapping, then review how those values are synchronized with other task managers; the work is complete only after the project settles on and validates either the four-level behavior or an explicit toggle.