feat(cli): support generics in fern definition (#4512)

* ready to go, merge from main

* prettier

* do not match on reserved keywords

* addressed comments

* no unused generic rule

* uncomment tests

* add no unused generics

* added rule for all non-aliases and all non-alias type contained values

* more test cases

* consolidate logic

* remove one more regex

* add more validation rules -- for number of applied arguments and if no arguments are applied

* add a couple more rules around number of args, no applied args

* chore(cli): reduce duplication with generic checks (#4525)

* addressed comments

* slightly cleaner error message

* added documentation and changelog version

* more real world example

* remove inlined literal

* more tangible example

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Co-authored-by: Deep Singhvi <[email protected]>

fix(cli): Substitute env vars before IR generation (#4520)

break(cli): require `generators.yml` to be present if using OpenAPI (…

…#4510)

fix(cli): allow service base path to be a slash (#4513)

fix(cli): openapi example generator handles circular `oneOf` schemas …

…(#4414)

chore(cli): release cli to produce ir v57.8.0

fix(cli): ir generation accurately generates examples for objects wit…

…h extends (#4408)

fix(postman): upgrade from ir v23 to ir v53 (#4378)

chore(cli): release 0.39.15 (#4381)

fix(cli): enforce date validation on date-type examples (#4358)

* fix(cli): enforce date validation on date-type examples

* different date definition, oops

* release ready

* update changelog