[ESLint Plugin] Enforce inclusion of dist-esm and exclusion of src in files field in package.json

[deyaaeldeen]

This change updates the ts-package-json-files-required rule to check for the absence of src and dist-esm in the files list in package.json since sourcemaps now have the sources embedded. It is based on discussion with @xirzec here #11273 (comment). Related issue: #7615.

TODO in this PR: update every package's package.json to conform to the final rule before merging.
After discussion with @willmtemple, @bterlson, and @xirzec here, this PR updates the eslint plugin to make sure dist-esm is included and src is not in package'json's files list.

[ramya-rao-a]

+1 on fixing all the package.json files in the same PR

[willmtemple]

I don't think we can remove dist-esm. External bundlers rely on having our ESM sources to build us for different targets like browsers, and our browser mappings rely on having the ESMs in the package.

[bterlson]

We should not remove dist-esm. It is not just for source mapping. It is preferred by bundlers. Some of the rationale is documented here, feel free to send a PR either updating this or removing the guideline with rationale!

[xirzec]

Let's change this to remove src but leave dist-esm\src

[deyaaeldeen]

Thanks @willmtemple, @bterlson, and @xirzec for the feedback! Please take another look.

Hi @XiaoningLiu, would you please confirm if source files need to be shipped in storage-datalake package? I am removing them here: 7af9e2e.

[willmtemple]

Left some comments with some nitpicks about code style and a couple of places where I think this could benefit from extra documentation, overall happy with the change to the linter's behavior.

[willmtemple]

Overall happy with this rule change, but I'd like to suggest making sure that this still works with packages that use shared code, such as keyvault (via keyvault-common) and storage. I think the output structure of their dist-esm is different due to the deeper-rooted source tree.

I think we should require all of dist-esm rather than just dist-esm/src.

[willmtemple]

This really helped clarify the purpose of the map above, thanks!

[willmtemple]

Just spoke with @deyaaeldeen and he clarified that the current behavior is not to requite dist-esm/src, but to use it as the default value, but anything that begins with dist-esm will be accepted. I'm good with that.