[BUG] `/model` ignores `ANTHROPIC_DEFAULT_OPUS_MODEL` with Bedrock global inference profiles

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When using /model to switch to Opus with Bedrock global inference profiles configured via ANTHROPIC_DEFAULT_OPUS_MODEL, Claude Code ignores the configuration and uses the region-specific model ID instead.

Configured: global.anthropic.claude-opus-4-6-v1
Actually used: us.anthropic.claude-opus-4-6-v1

What Should Happen?

The /model command should respect the ANTHROPIC_DEFAULT_OPUS_MODEL environment variable and use the configured global inference profile ID.

Error Messages/Logs

Steps to Reproduce

1. Configure ~/.claude/config.json:

```json
{
"env": {
"AWS_REGION": "us-west-2",
"AWS_DEFAULT_REGION": "us-west-2",
"CLAUDE_CODE_USE_BEDROCK": "1",
"ANTHROPIC_DEFAULT_OPUS_MODEL": "global.anthropic.claude-opus-4-6-v1"
}
}

1. Start Claude Code
2. Run /model and select Opus
3. Observe that us.anthropic.claude-opus-4-6-v1 is used instead of the configured global.anthropic.claude-opus-4-6-v1

Claude Model

Not sure / Multiple models

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.37 (Claude Code)

Platform

AWS Bedrock

Operating System

macOS

Terminal/Shell

Other

Additional Information

The /model command appears to have region inference logic that overrides explicit global inference profile configurations. This prevents using cross-region global profiles via the /model command.