[FEATURE] Avoid shell quoting issues when passing markdown to CLI tools like gh

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

Failed commands (sometimes long chains) fail often in workflows because of quoting/escaping issues. This happens often.

See #29619. It says to make a new issue if this is still an issue, so here it is.

Proposed Solution

See #29619. Alternately, have Fable 5 think about it. (Though it is currently tragically unavailable.)

Alternative Solutions

Current workaround is tempfile creation, which wastes tokens and introduces filesystem churn.

Priority

High - Significant impact on productivity

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_