Create broad-based testing suite for aria2tui

[grimandgreedy]

We need to establish a base set of cases that are required for aria2tui, establish a way of creating a test aria2tui within the testing environment, and test the core functionality. This is a high priority as when we add core functionality or refactor menu options we need a quick way to test that everything still works as expected.

We have a working approach using pytest with kitty and IPC which can launch aria2tui and pass keys to the curses interface and confirm certain output. We need to figure the best way to either start an aria2c daemon with a test config or mock the daemon.