[FEATURE] Add Max thinking option for Claude Opus 4.6

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Add Max thinking option for Claude Opus 4.6. The Max thinking option is available in the api but not in Claude Code, please add it.

Proposed Solution

Add Max thinking option for Claude Opus 4.6. The Max thinking option is available in the api but not in Claude Code, please add it.

Alternative Solutions

_No response_

Priority

High - Significant impact on productivity

Feature Category

CLI commands and flags

Use Case Example

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Additional Context

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