Add astronomical units to length unit convert

[Veloctor]

Problem Statement
Add Light year (ly) and Astronomical unit (AU) and Parsec (pc) to length unit convert. 1ly = 9460730472580800 m, 1AU=149597870700 m. 1pc = 648000/π AU.

Evidence or User Insights
Calculator on Xiaomi phones already has this function, I want Windows PC also built in this function.

Proposal
Astronomer or Astronomical enthusiasts, sometimes want to know how far apart are two stars in meters.

Goals
For example, when I develop game or do scientific computation, I need to know what is the absolute error of double precision fp representing the distance between two stars, so I need to calculate x ly / 2^53, and convert the number to meter. Now I need to send the number to my Xiaomi phone and copy to Calculator to do this, or run Visual Studio to create a C# program to do this. Obviously just use Windows Calculator is way more efficient, right?

Low-Fidelity Concept
No, description above is clear enough.

Requested Assignment
I'm just suggesting this idea. I don't want to implement it.

Note: I noticed that this function has been mentioned in issue #325 in 2019, and finally it was merged into #515 , but it has not yet been implemented. If #515 is planned to be implemented after a long time, I hope to add these three units offline to the calculator first.

[Veloctor]

No one seems to implement this function. I will do it myself.