Add back unqualified tsconfig.json files to each package that references
both the Node.js build and the browser build. This makes tsc --build
compile both builds when the variant to do is not specified.
Distinguish the Node.js build in the same way the browser build is with
the .node suffix to the tsconfig files it uses. This means
tsconfig.node outputs to dist/node and tsconfig.browser outputs to
dist/browser.
Use a separate folder for the TypeScript build for Node.js in the dist
folder. This makes each type of build consistently have its own output
folder instead of being interleaved with the Node.js build.
Fix coverage checking not being able to deduce the original TypeScript
files due to lacking a way to link the compiled .js output files with
the .ts input files.
Hornwitser