feat(dynamite): Support decoding booleans

[provokateurin]

No description provided.

[Leptopoda]

Is this something we need immediately or just a nice to have?

As this isn't really openapi conformant I'd like to have this behind an option or specify custom types (see #749). In that case let's talk about it next week.

[provokateurin]

I had this problem with the generated Talk spec, I don't remember exactly in what context this occurred 😅

[provokateurin]

I remember what this was used for: Booleans in headers
We now have the problem that this is also present in the core of Nextcloud server, so we need to support this in some way.
As far as I can tell this has to be fully supported since headers are just a normal OpenAPI schema.
I'm not sure how to proceed with this 🤔

[provokateurin]

As far as I can tell this is expected behavior. https://swagger.io/docs/specification/describing-parameters has an example which encodes a boolean as literal true and https://github.com/stoplightio/elements (which Nextcloud uses to render the OpenAPI documentation) also does this when sending requests or generating code snippets.
The encoding part doesn't need to be updated because it already works ootb when calling toString() on a Dart boolean.

[Leptopoda]

LGTM.
It'll probably be changed a bit with the DynamiteRawResponse