Add the ability to specify a default timeout if the header was not received or was incorrect

[ulbwa]

something like

countdown: DeadlineCountdown(default_timeout=float)

[ulbwa]

For now it is possible to specify default_timeout for process middleware, which will perform exactly this. DeadlineCountdown is an annotation, so need to rewrite it into a function that will return an annotation. The question is how to get this default_timeout from the parameter in DeadlineCountdown

[ulbwa]

Moreover, functions cannot be called in type annotations, so this needs to be implemented either through Annotated metadata or as a default parameter value, e.g, countdown: DeadlineCountdown = DefaultCountdown(float) or Annotated[DeadlineCountdown, DefaultCountdown(float)]. We can get signature from context.get("handler_"), but I don’t understand how to retrieve the “filtered” handler, and there may be more than one. It seems that the simplest way would be to implement a mapping of the subject to a default timeout in process middleware args