fix: add missing exports from packages

[clavin]

• I have read the contribution documentation for this project.
• I agree to follow the code of conduct that this project follows, as appropriate.
• The changes are appropriately documented (if applicable).
• The changes have sufficient test coverage (if applicable).
• The testsuite passes successfully on my local machine (if applicable).

Summarize your changes:

Exports various interfaces from packages who were missing them. This causes docs to be generated for those symbols as well.

This also adds a plugin so default exports aren't just named default 😬 (although, there is no indicator that they are the default export either)

[malept]

Add a comment explaining why it's being exported? Otherwise looks fine.

[codecov]

Codecov Report

Merging #2920 (5a74bd4) into master (345250c) will decrease coverage by 0.38%.
The diff coverage is 14.28%.

@@            Coverage Diff             @@
##           master    #2920      +/-   ##
==========================================
- Coverage   71.82%   71.43%   -0.39%     
==========================================
  Files          79       79              
  Lines        2385     2412      +27     
  Branches      449      450       +1     
==========================================
+ Hits         1713     1723      +10     
- Misses        450      466      +16     
- Partials      222      223       +1     

Impacted Files	Coverage Δ
packages/installer/deb/src/InstallerDeb.ts	50.00% <0.00%> (-16.67%)	⬇️
packages/installer/dmg/src/InstallerDMG.ts	28.57% <0.00%> (-1.43%)	⬇️
packages/installer/exe/src/InstallerExe.ts	60.00% <0.00%> (-15.00%)	⬇️
packages/installer/rpm/src/InstallerRpm.ts	50.00% <0.00%> (-16.67%)	⬇️
packages/installer/zip/src/InstallerZip.ts	35.71% <0.00%> (-2.75%)	⬇️
packages/maker/appx/src/MakerAppX.ts	60.34% <0.00%> (-0.37%)	⬇️
packages/maker/deb/src/MakerDeb.ts	90.90% <0.00%> (-4.10%)	⬇️
packages/maker/dmg/src/MakerDMG.ts	95.00% <0.00%> (-5.00%)	⬇️
packages/maker/pkg/src/MakerPKG.ts	92.85% <ø> (ø)
packages/maker/rpm/src/MakerRpm.ts	90.90% <0.00%> (-4.10%)	⬇️
... and 16 more

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