Subclass Out GUI Nodes from Runner

[raymondwjang]

IMPORTANT

Critical to keeping the package maintainable and extensible.

Background

Currently, the GUI nodes are hardcoded into the Runner class. (The nodes get initialized in __post_init__ of Runner and are hardcoded in prep and iter of Runner)

This is going to cause a major case of spaghetti code that is unmaintainable, as Runner is violating SRP by technically initiating GUI communication and running WebSocket/video encoding processes.