I built a Mac app after getting surprised by my...

A few months back I got my monthly API bill and felt sick. I had been vibe-coding pretty hard with Claude, and I knew it wasn't going to be zero. But the number was way higher than I expected. Like, embarrassingly higher. I had been running Claude Code sessions back to back, long context windows, lots of tool calls, and I had no idea how fast it was adding up. The worst part? I couldn't have known. There's no live feedback. You just work, and then you find out later. So I did what most developer