Incorporating deadline into UART/writer interfaces in MicroZig

[mattnite]

Quick question that popped up when using the interfaces. Is this deadline correct? It's initialised when instantiating the Reader struct, but at least for the RP2040 I'm creating these deadlines with time.deadline_in_ms() which simply adds the argument with the current time to define an absolute timestamp when the deadline elapses.

Now, given the deadline's instantiated at the very beginning and never recreated it basically becomes a no-op as it's always elapsed later down the road.

Would it make sense to instead of passing an instantiated mdf.time.Deadline pass an integer (i.e. deadline_ms) to instantiate the deadline whenever we make a call such as a in stream()?

Maybe I'm just using the API wrong...

Should this be an error I'd be more than happy to provide a separate PR handling this as it affects both the Reader and Writer.

Thanks a ton for your time.

Originally posted by @pcolladosoto in #1008

[Grazfather]

We definitely want to support deadlines, and we want them to work as advertised.

That said, that would probably mean that clients end up manually resetting the deadline for every read/write call. We could make this easier with a method.

Another option (and we could do both) is to have the deadline field be a union with something like a default_timeout. If that field is active, then we create a new deadline on each call .from_timeout.