feat: invert call.Direct

[pd93]

The API for taskfile/ast.Call.Direct isn't great when using Task as a Go package. Creating a task as if it were being called from the CLI means you have to write something like this:

call := ast.Call{Task: "default", Direct: true}

I can't think of many situations where you would want to set Direct: false from an API as this mainly intended for internal use when parsing a ast.Cmd or ast.Dep. Additionally, it's easy to forget to add Direct: true and omitting it is probably not the behaviour you want.

If we invert the property name from Direct to Indirect, the default value becomes false and so when calling a task with the API you would simply need to do:

call := ast.Call{Task: "default"}

[andreynering]

Better, indeed. Thanks!