Add support for TypeScript config files (.size-limit.ts, .size-limit.mts, .size-limit.cts)

[aryaemami59]

This PR:

• Adds jiti as a dependency.
• Adds support for loading TypeScript config files (.size-limit.ts, .size-limit.mts, .size-limit.cts).
• Adds fixtures to test every single file extension/module type combo to make sure the library is fully capable of handling different configuration flles.
• Test performance to make sure extra overhead was not accumulated.
• Adds unit tests to test edge cases.

[ai]

You may want to add *.d.ts file to c8 config to move it from coverage check

[ai]

Thanks. Released in 11.1.

[aryaemami59]

@ai Awesome thank you so much!