Add 'World::run_system_with_input' function + allow World::run_system to get system output#10380

alice-i-cecile merged 6 commits intobevyengine:mainbevyengine/bevy:mainfrom

Nathan-Fenner:nf/run_system_with_inputNathan-Fenner/bevy:nf/run_system_with_inputCopy head branch name to clipboard