Personally, IDE for the agent era is just Linux.

Kitty with oh-my-zsh, lazyvim and an agent. The entire thing is an ide. If I need to refactor, query data and interact with the system I just use native tools like rg+fastmod, bash, awk, jq... Either writing myself of asking an agent to do the heavy lifting.

Linux in the agent era is a breeze to operate and reason about, so the whole thing becomes a single development environment that's really light on resources and effective.