[Feature Request] Allow selection of Claude model versions (e.g., claude-opus-4.6)

Question

**Bug Description**
there has been substantial regression (reasoning/memory/context/tool usage) in the opus models 4.7 and 4.8 ... is there a way to choose to use the opus 4.6 model (which was the last time I remember opus actually being usable)? If not, can anthropic please allow an    option to choose model version?

**Environment Info**
- Platform: darwin
- Terminal: Apple_Terminal
- Version: 2.1.166
- Feedback ID: b87fb710-4fa6-4869-8680-bdb37c710db4

**Errors**
```json
[]
```