[FEATURE] CLAUDE_CODE_OUTPUT_STYLE env var

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

outputStyle can be set in user, project, or managed settings, but there's no env-var override — same gap as permissions.defaultMode.

Proposed Solution

Add CLAUDE_CODE_OUTPUT_STYLE env var, mirroring CLAUDE_CODE_EFFORT_LEVEL's precedence and semantics.

Alternative Solutions

• /output-style per session
• Editing user settings directly

Priority

Low - Nice to have

Feature Category

Configuration and settings

Use Case Example

Per-machine output-style personalization (e.g., terse on laptop, verbose on workstation) without modifying shared project or managed settings.

Additional Context

_No response_