'model' field in slash command appears to be ignored [Version: 0.6.4] #2460

Description

The model field in slash command YAML frontmatter appears to be ignored, causing commands to fall back to the default model without any user notification.

This is documented in the [commands[(https://opencode.ai/docs/commands/) section of the docs, suggesting that the docs are out of sync.

Steps to Reproduce

1. Create .opencode/command/test.md:

   ---
   description: "Test command with specific model"
   agent: plan
   model: cerebras/qwen-3-coder-480b
   ---
   
   This is a test command.

2. Run the command: /test

3. Observe that the command executes with the default model instead of the specified model

Tested with cerebras/qwen-3-coder-480b, github-copilot/claude-sonnet-4 and anthropic/claude-sonnet-4-20250514. Neither of the 3 models worked in the 'model' field.