get_window().grab_focus() was insufficient on Windows GUI exports.
Replaced with OS.move_to_foreground() + Input.set_mouse_mode(CAPTURED)
+ deferred retries to ensure the game window holds keyboard focus
after the connection UI is dismissed.
Added explicit window focus grab after connecting (lan-bootstrapper.gd)
so keyboard input is properly received by the input system.
Also added diagnostic debug prints to trace input pipeline.
lan-bootstrapper.gd and noray-bootstrapper.gd both had a host_only()
function that referenced BrawlerSpawner (class_name from forest-brawl).
Since examples/forest-brawl/ is excluded from exports, the type was
undefined, causing the entire script to fail loading with:
'Could not find type BrawlerSpawner in current scope'
This meant the Join and Host button signal handlers never existed,
so clicking them did nothing — no error shown, no connection, no UI change.
Fix: remove the unused host_only() function from both bootstrapper files.