The number of arguments to a function has a limit.

# Effect

Very large messages being sent back to the GUI failed with a stack overflow error.

## Fix

Relying on splatting an array into function arguments to limited by the maximum no of possible arguments to a function. Hence very large messages being sent back to the GUI would fail with a stack overflow error.
Making them arrays removes this limitation.

#### Notes

I discovered this while working on the TCP conversion since I've been using very large packet sizes to run tests.