Feature: ESM exports support

[ryan-roemer]

Work

• Support ESM package.json:exports in Modern Node.js (CJS and ESM style). Fixes Test Scenario: New Node.js ESM packages. #51

Related follow-on work

• Feature: Add user-specified conditions to ESM resolution. #56 Support user-specified conditions
• Feature: Support advanced Node.js ESM import types. #57 Support advanced Node.js ESM import types

Tasks

• Handle https://unpkg.com/browse/[email protected]/package.json which currently blows things up.
• Add documentation section discussing how it all works to README
• Review and remove all TODOs
• Review original ticket and ticket out future work / scenarios

[codecov-commenter]

Codecov Report

Merging #55 (d23ec56) into main (c91df16) will increase coverage by 0.07%.
The diff coverage is 98.01%.

@@            Coverage Diff             @@
##             main      #55      +/-   ##
==========================================
+ Coverage   98.41%   98.49%   +0.07%     
==========================================
  Files           5        6       +1     
  Lines         253      332      +79     
==========================================
+ Hits          249      327      +78     
- Misses          4        5       +1     

Impacted Files	Coverage Δ
lib/trace.js	98.87% <97.26%> (-0.34%)	⬇️
lib/package.js	100.00% <100.00%> (ø)
lib/path.js	100.00% <100.00%> (ø)

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[ryan-roemer]

@bmathews @tptee -- This PR is ready for review / tire-kicking and should handle both of your respective project situations where ESM is giving you grief. Appreciate a review and any feedback!!!

[bkonkle]

Looks good in our project. Very minor size differences. 👍

[tptee]

Works for our troublesome package now 🙌

[ryan-roemer]

Released in [email protected]