The previous documentation implied that categories automatically use their
built-in default models (e.g., Gemini for visual, GPT-5.2 for ultrabrain).
This was misleading. Categories only use built-in defaults if explicitly
configured. Otherwise, they fall back to the system default model.
Changes:
- Add explicit warning about model resolution priority
- Document all 7 built-in categories (was only showing 2)
- Show complete example config with all categories
- Explain the wasteful fallback scenario
- Add 'variant' to supported category options
Fixes confusion where users expect optimized model selection but get
system default for all unconfigured categories.
Co-authored-by: DC <vmlinux@p16.tailnet.freeflight.co>
7f43f160b5