feat: compress partial transcript

[themighty1]

This PR enables the prover to compress the partial transcript when sending it to the verifier.

Also renames the field PartialTranscript::sent_authed to sent_authed_idx to minimize cognitive burden when analyzing the compression logic.

[codecov]

Codecov Report

Attention: Patch coverage is 95.06173% with 4 lines in your changes missing coverage. Please review.

Project coverage is 55.95%. Comparing base (7bec5a8) to head (1646a6b).
Report is 1 commits behind head on dev.

Files with missing lines	Patch %	Lines
crates/core/src/transcript.rs	95.06%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              dev     #653      +/-   ##
==========================================
+ Coverage   55.74%   55.95%   +0.21%     
==========================================
  Files         189      189              
  Lines       20769    20813      +44     
==========================================
+ Hits        11577    11646      +69     
+ Misses       9192     9167      -25     

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[yuroitaki]

Great work!