Migration from Claude Code to a private local harness. Questions.

I'll start by saying I'm not talking about the models themselves, I'm aware that I can't come close to something like Fable's intelligence locally. Just wanted to get that out of the way. Basically. Over the last year I've gotten quite comfortable with claude code, and it seems likely there were be a gradual cost rug pull, and I'd like to put myself in a better position when that happens for local use. I am already used to running local models (such as Qwen3.8_Q5) in things like lmstudio, but I have no experience with other harnesses. I'd like to know, what harness, right out of the box would feel most at home for current Claude Code users. I say this as someone who was not coding prior to "vibe coding". I'm looking for the path of least resistance, though I will no doubt eventually spread out into tools that give me more control. But for now, I'm just looking for a life raft. Just needs to be local, opensource, and free of spyware. In case someone wants to know 24GB VRAM (rtx 3090) and 64GB DDR4.