[BUG] Shell snapshot incorrectly captures aliases starting with `-`, causing syntax error

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?

Claude Code's shell snapshot mechanism incorrectly captures bash aliases that start with a hyphen (-), resulting in malformed alias syntax and causing an error every time a shell command is executed.

What Should Happen?

Expected Behavior

The snapshot should preserve the correct alias syntax:
alias -- -='cd -'

Actual Behavior

The snapshot incorrectly duplicates the -- option terminator:
alias -- -- -='cd -'

Error Messages/Logs

This causes the following error on every shell command execution:
.claude/shell-snapshots/snapshot-bash-XXXXX.sh: line 4202: alias: --: not found

Steps to Reproduce

1. Define a valid bash alias that starts with - in your shell config:

```bash
alias -- -='cd -'
This is the standard bash syntax for defining aliases beginning with a hyphen.

1. Run any command through Claude Code
2. Claude Code creates a shell snapshot in ~/.claude/shell-snapshots/
3. The snapshot file contains malformed alias syntax

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.0.71

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Other

Additional Information

_No response_