Salam.
I'm currently working on a very similar idea but through a no code UX perspective https://usetwobytwo.com.
Nice to see you guys see the same issue exist.
I used Cursor with Opus but was expensive. I've moved to Zed with Claude max plan and have enjoyed the fast editor and get way more out of my Max plan. Zed offers enough inline suggestions for free.
+1 for Tanstack start. I just setup a new project with it and like the whole ecosystem. Only slight disadvantage is most third party documentation and automatic setup with packages aren't setup for Tanstack Start yet.
I used Charles to help me get endpoints for controlling my automatic cat toilet. The Chinese based iOS app was horrible to use and who knows what data it collected.
After getting the endpoints, I was able to plug it directly into Home assistant.