feat(extract): makes support for subpath imports explicit

[sverweij]

Description

• ensures that subpath imports are recognized as 'aliased', just like the webpack and tsconfig aliases & import paths.
• splits out the 'aliased' dependency type into three (while leaving the 'aliased' one in place both for convenience and backwards compatibility): aliased-subpath-import, aliased-webpack, aliased-tsconfig
• modifies the moreThanOneDependencyType rule/ matcher so ...
  • it doesn't count aliases as separate dependency types (see documentation for rationale)
  • it doesn't count type-only as separate dependency types (also: see documentation)

TODO: subpath imports can resolve to local modules ("#*": "./src/*"), but also to 3rd party modules ("#aliasdash/*": "lodash/*") or even core modules (which should be considered a criminal offence and is currently not even recognized in enhanced-resolve: "#path-but-aliased": "path"). These should be added to the dependencyTypes array as well - will probably be in a separate PR, though.

Motivation and Context

subpath imports work since node 12.9 (!) and are a vastly superior alternative to tsconfig paths other alias systems (in webpack, babel, ...):

• there's native support for it in nodejs, typescript (recent versions) and most other bundler/ packager under the sun.
• This means it doesn't require third party shims/ polyfills, which is good for site reliability.

Dependency-cruiser already correctly resolved subpath imports - this PR ensures they're explicitly named as such.

How Has This Been Tested?

• green ci
• additional automated non-regression tests
• updated automated non-regression tests

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• Documentation only change
• Refactor (non-breaking change which fixes an issue without changing functionality)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• 📖

  • My change doesn't require a documentation update, or ...
  • it does and I have updated it

• ⚖️

  • The contribution will be subject to The MIT license, and I'm OK with that.
  • The contribution is my own original work.
  • I am ok with the stuff in CONTRIBUTING.md.

[codeclimate]

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