refactor!: make encode and decode traits more symmetric

[danieleades]

closes ##78

[danieleades]

could you review @DCNick3 ?

[codecov]

Codecov Report

❌ Patch coverage is 83.33333% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 87.57%. Comparing base (b19b329) to head (44f4479).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/encoder.rs	83.33%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #112   +/-   ##
=======================================
  Coverage   87.57%   87.57%           
=======================================
  Files          11       11           
  Lines         483      483           
=======================================
  Hits          423      423           
  Misses         60       60           

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[DCNick3]

These API changes look fine to me.

I wanted to try the new API out by porting my usage of arithmetic-coding to the new API, but I found out I ended up only using arithmetic-coding-core, so I can't give you any usability insights.

P.S the reason I decided against using arhithmetic-coding was mostly because I didn't like to have a dependency on bitstream-io and I wanted to write into a bignum instead of a byte stream. You can see it here: https://github.com/DCNick3/baam-compressed-token.

[danieleades]

These API changes look fine to me.

I wanted to try the new API out by porting my usage of arithmetic-coding to the new API, but I found out I ended up only using arithmetic-coding-core, so I can't give you any usability insights.

P.S the reason I decided against using arhithmetic-coding was mostly because I didn't like to have a dependency on bitstream-io and I wanted to write into a bignum instead of a byte stream. You can see it here: https://github.com/DCNick3/baam-compressed-token.

i'm not actually using much of the api surface of bitstream-io, so i could probably make this library a little more flexible without too much trouble