If we take Zi Mei for example (R commit 1 foundation: after you play an attack, not as block, commit 1 card in your opponent's staging area) after playing an attack can i pay Zi Mei's R cost by committing shinobi tradition and then ready it because i have just played an attack? I am not sure if the timing is right.

i would think so its all in the same trigger phase

You can, you can also play any other abilities that respond to a card being played.