October AI model refresh

The model picker now includes:

• Anthropic Sonnet 5.5 and Haiku 5.5
• OpenAI GPT 6.1 Sol and Sol Pro
• Mistral Large 4
• Cohere Command A+
• Fireworks Ember-1
• Qwen 3.8 Max Prime
• Upstage Solar Mini 4
• Z.ai GLM 5.3 Prime

We've also updated per-message credit costs across the catalog. Review the available models and their credits in Settings → AI models.