[MRG] create ComputeParameters.from_manifest_row in support of sourmash sketch fromfile

[ctb]

This PR is in support of #1885.

This PR refactors manifest row extraction into ComputeParameters.from_manifest_row.

[codecov]

Codecov Report

Merging #1886 (94357a8) into latest (8f4c94c) will increase coverage by 7.89%.
The diff coverage is 84.21%.

@@            Coverage Diff             @@
##           latest    #1886      +/-   ##
==========================================
+ Coverage   82.64%   90.54%   +7.89%     
==========================================
  Files         121       91      -30     
  Lines       13148     8957    -4191     
  Branches     1772     1774       +2     
==========================================
- Hits        10866     8110    -2756     
+ Misses       2017      581    -1436     
- Partials      265      266       +1     

Flag	Coverage Δ
python	90.54% <84.21%> (-0.02%)	⬇️
rust	?

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Impacted Files	Coverage Δ
src/sourmash/command_sketch.py	88.20% <50.00%> (-0.39%)	⬇️
src/sourmash/command_compute.py	92.45% <88.23%> (-0.24%)	⬇️
src/core/src/from.rs
src/core/src/ffi/utils.rs
src/core/src/sketch/hyperloglog/estimators.rs
src/core/src/signature.rs
src/core/src/index/mod.rs
src/core/src/ffi/signature.rs
src/core/src/encodings.rs
src/core/src/ffi/index/revindex.rs
... and 22 more

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[ctb]

@sourmash-bio/devs ready for review and merge!