[TS] Fix relative import paths of generated TypeScript code

[auschi-shieldai]

This PR fixes two issues:

• Resolves an issue where relative import paths are not generated correctly for dependents with no namespace
• Refactors how relative imports are generated, removing the need to back out multiple, unnecessary directory levels

A new test suite has been added to validate relative import paths, as well as the fix itself.

This PR also sneaks a couple linting/formatting fixes in for unrelated parts of the idl_gen_ts.cp file.

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[bjornharrtell]

Looks good to me!

[bjornharrtell]

@auschi-shieldai sorry this has been taking so long but I'd like to help get this moving now... however, it now needs resolve conflicts with main. Is that something you can do?

[auschi-shieldai]

@auschi-shieldai sorry this has been taking so long but I'd like to help get this moving now... however, it now needs resolve conflicts with main. Is that something you can do?

@bjornharrtell no worries at all!

I'll get the merge conflicts resolved here in the next couple of hours and re-request your review once changes are pushed up.

Thank you!

[bjornharrtell]

@auschi-shieldai sorry but seems something isn't right (see test failures)

[auschi-shieldai]

@bjornharrtell I'm a little swamped today, so I plan on taking a look and getting it fixed later tonight. I imagine something got a little funky after resolving those merge conflicts