[FEAT] Add encoding module in `lib_ccxr`

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Closes #1554

Added a module in lib_ccxr for working with different kinds of text encoding formats. This PR adds types used for representing Strings encoded in a certain format like Line 21 or UCS-2 and the ability to interconvert between them.

CCExtractor / ccextractor

[FEAT] Add encoding module in `lib_ccxr` #1628