feat: logic blocks v5 (serialization, optional diagram generation, boxless input queing, allocation-free hot path, type registry, etc)

[definitelyokay]

• Reduces abstractions and eliminates a number of generics and nested classes.
• Automatically infer OnEnter/OnExit type correctly via capturing generics from extension methods. No more bugs because you specified the wrong type! Only change is that you need to call this.OnEnter((State? previous) => ...) instead of OnEnter<StateType>((previous) => ). There's also overloads that don't require you accept the previous/next state if you don't need it (99% of use cases).
• Updates the diagram generator to support syntax changes.
• [StateMachine] is now [LogicBlock(typeof(ConcreteState), Diagram = true)].
• Refactors the example to demonstrate a conventional logic block state structure.
• Eliminates the complex Use selector binding that I never actually used in practice. If you were using it, sorry! I needed to eliminate the dependency on Microsoft.CSharp, and the features it was using with dynamic required that package. From what I learned, those bindings wouldn't be AOT-friendly, and all Chickensoft packages need to be AOT-friendly.
• Eliminates boxing inputs and outputs altogether, even in the bindings system. This means that the single input handler execution hot path is allocation-free!
• A single input never hits the heap now! An input is only queued if another input is already being processed.
• Pass all inputs and outputs by reference via in
• Updates start/stop logic to be more correct.
• No more lambda allocations when executing enter/exit or attach/detach callbacks.
• Introduces a new source Introspection generator that registers all visible types and generates additional metadata information about types tagged with the [Introspective] attribute.
• Adds a Serialization package that provides a type resolver for introspective types which supports polymorphic deserialization with 0 configuration.
• Adds a LogicBlockConverter that can serialize and deserialize logic blocks and their blackboards.