Replace enum extraction with CasePath

[kmcbride]

Replaces enum extract via Mirror to instead use CasePaths, which should boost performance.

I cherry-picked the relevant pieces, consolidated them into a single file, and tweaked a few access levels to keep the types internal.

[codecov]

Codecov Report

Merging #181 (db8c302) into master (142cf70) will increase coverage by 0.58%.
The diff coverage is 100.00%.

❗ Current head db8c302 differs from pull request most recent head fb357ca. Consider uploading reports for the commit fb357ca to get more accurate results

@@            Coverage Diff             @@
##           master     #181      +/-   ##
==========================================
+ Coverage   95.55%   96.14%   +0.58%     
==========================================
  Files          43       42       -1     
  Lines        1462     1425      -37     
==========================================
- Hits         1397     1370      -27     
+ Misses         65       55      -10     

Flag	Coverage Δ
ios	?
macspm	96.14% <100.00%> (+0.62%)	⬆️

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Impacted Files	Coverage Δ
MobiusCore/Source/EffectHandlers/EnumRoute.swift	83.33% <100.00%> (+15.76%)	⬆️
...rowableAssertion/Source/MobiusThrowableAssertion.m

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