Add astronomical units to length unit convert

[Veloctor]

Description of the changes:

-Add Light year (ly) and Astronomical unit (AU) and Parsec (pc) to length unit convert, with all language localizations generated by ChatGPT. 1ly = 9460730472580800 m, 1AU=149597870700 m. 1pc = 648000/π AU. #2359

How changes were validated:

Run tests. If you like, check ISO standard defintion about these units.

Specify how you tested your changes:

• Manual test, validate au/pc/ly to meters converted value.
• Add test case to src\CalculatorUnitTests\Test.resw, and run tests.

[Veloctor]

@microsoft-github-policy-service agree