Yeah, it does seem vibecoded or at least not really qa'd, but on the flip side this produces the more or less the exact calendar template I've been looking for for a while.
I think this app really speaks to the value of AI driven coding - it's clearly less polished than what an experienced SWE would produce given several days of time but at the same time offers real value and solves a niche problem.
Thanks for sharing OP, will use the app!