is it possible to set @turbo thread = true/false at runtime?

I have a function that uses @turbo and has a threaded kwarg

```julia
function f(a, b; threaded = true)
c = similar(a)
@turbo thread = true for i = eachindex(a)
c[i] = a[i]+b[i]
end
end
```

is it possible to pass the function kwarg `threaded` to `@turbo` to set `thread ` ?

Start by examining the @turbo macro entry point and how it handles the thread=true option in the shown function f. Determine whether the threaded keyword can control that option at runtime, and document or implement the supported behavior with a focused test if the repository provides one.

Scritto dal modello di indicizzazione a partire dal testo della issue.