chore: support for dotenv switching

[rot1024]

yarn start # loads .env
yarn start --env local # loads .env.local (NEW!)

[netlify]

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[codecov]

Codecov Report

Merging #106 (f8abf58) into main (da48150) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #106   +/-   ##
=======================================
  Coverage   53.53%   53.53%           
=======================================
  Files          48       48           
  Lines         891      891           
  Branches      119      119           
=======================================
  Hits          477      477           
  Misses        364      364           
  Partials       50       50