On my “ToDo” list I have a “Write some ‘WindowWrangler’ thingie” item just for that “snap windows to corner/sides” features… too bad I’m too lazy, but also…
This thread reminded me that @zuMi’s winpwnr.sh exists (notice the “-n” parameter in particular). That script was disscussed here: Haiku scripting.
I bet one can use that along with the “Shortcuts” preflet to have something working.