Workflow tool rejects ordinary CRLF line endings as "hidden control characters"

### Preflight Checklist

- [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) 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?

Version: Claude Code 2.1.226, Windows 11

Summary: Calling the Workflow tool on a script file that uses Windows-style CRLF line endings fails with a permission-schema-validation error claiming the script contains control characters that would be hidden in the approval dialog. The only "control characters" present are \r bytes forming standard CRLF line endings — there is no injected, zero-width, or otherwise genuinely hidden content.

Repro:

Save any valid workflow script to .claude/workflows/foo.js with CRLF line endings (the Windows default when git config core.autocrlf is true, or from any Windows-native editor).
Call Workflow({ name: "foo" }).
Observe: The permission handler returned updatedInput for Workflow that failed schema validation: script contains control characters that would be hidden in the approval dialog.
Converting the same file to LF-only line endings (byte-identical otherwise) resolves the error.

### What Should Happen?

Expected: \r as part of an ordinary CRLF pair should not be flagged as a "hidden control character" — it renders as a normal line break, not an invisible or disguising character. The check appears to be flagging any \r/control byte unconditionally rather than distinguishing conventional line-ending bytes from genuinely suspicious ones (zero-width joiners, RTL overrides, mid-line control codes).

Impact: Any .claude/workflows/*.js file with CRLF line endings — the Windows-checkout default — cannot be invoked via Workflow at all, with no workaround short of manually stripping \r bytes (and pinning .gitattributes to prevent git from reintroducing them on the next checkout).

### Error Messages/Logs

```shell

```

### Steps to Reproduce

Repro:

Save any valid workflow script to .claude/workflows/foo.js with CRLF line endings (the Windows default when git config core.autocrlf is true, or from any Windows-native editor).
Call Workflow({ name: "foo" }).
Observe: The permission handler returned updatedInput for Workflow that failed schema validation: script contains control characters that would be hidden in the approval dialog.
Converting the same file to LF-only line endings (byte-identical otherwise) resolves the error.

### Claude Model

None

### Is this a regression?

Yes, this worked in a previous version

### Last Working Version

_No response_

### Claude Code Version

2.1.226

### Platform

Anthropic API

### Operating System

macOS

### Terminal/Shell

Terminal.app (macOS)

### Additional Information

_No response_

Start with the Workflow tool and its permission handler, using .claude/workflows/foo.js to reproduce the failure with CRLF and LF-only line endings. Confirm that ordinary CRLF files are accepted while genuinely suspicious control characters remain rejected, and verify the permission-schema validation succeeds for the CRLF case.

Written by the indexing model from the issue text.