refactor: ts helpers api

[Dario-DC]

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• My pull request has a descriptive title (not a vague title like Update index.md)

Closes #XXXXX

This PR refactors the methods listed below into properties to simplify the API.

Old	New
getVariables()	variables
getValue()	value
getAnnotation()	annotation
getFunctions()	functions
getFunctions(true)	allFunctions
getParameters()	parameters
getTypeParameters()	typeParameters
getTypeArguments()	typeArguments
getTypes()	types
getInterfaces()	interfaces
getClasses()	classes
getMethods()	methods
getConstructor()	classConstructor
getClassProps()	classProps
getClassProps(true)	constructorProps
getTypeProps()	typeProps
getObjectProps()	objectProps

[ojeytonwilliams]

LGTM 👍