[BUG] sandbox auto-allow does not work vor env-prefixed commands

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?

In /sandbox mode, with auto-allow on, normal bash commands are auto-approved, but not those prefixed with an environment variable.

What Should Happen?

They should be allowed as well, as they used to be in a previous version.

Error Messages/Logs

Steps to Reproduce

╭─── Claude Code v2.1.112 ──────────────────────────────────────────────────────────────────────────────────╮
│                                                    │ Tips for getting started                             │
│                Welcome back Joachim!               │ Ask Claude to create a new app or clone a repository │
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│                       ▐▛███▜▌                      │ Recent activity                                      │
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│                        ▘▘ ▝▝                       │                                                      │
│   Opus 4.7 (1M context) with xh… · Claude Max ·    │                                                      │
│   mail@joachim-breitner.de's Organization          │                                                      │
│                   ~/claude-test                    │                                                      │
╰───────────────────────────────────────────────────────────────────────────────────────────────────────────╯

❯ /sandbox
  ⎿  ✓ Sandbox enabled with auto-allow for bash commands

❯ I believe we have a bug in claude cli: Even with /sandbox in auto-allow, commands that set environment variables are not auto allowed. This used to work in a previous version. Can you
  demonstrate that bug by runing a harmless command like cwd in the sandbox, and then try to run `SOME_VAR=true`.

● Bash(pwd)
  ⎿  /home/joachim/claude-test

● Bash(SOME_VAR=true)
  ⎿  (No output)

● The first command (pwd) ran auto-allowed in the sandbox. The second (SOME_VAR=true) — if you saw a permission prompt, that demonstrates the bug: a pure env-var assignment triggers approval
  instead of being auto-allowed under /sandbox.

❯ I meant `SOME_VAR=true pwd`

● Bash(SOME_VAR=true pwd)
  ⎿  Running…

────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 Bash command

   SOME_VAR=true pwd
   Run pwd with an environment variable set

 This command requires approval

 Do you want to proceed?
 ❯ 1. Yes
   2. Yes, and don’t ask again for: SOME_VAR=true pwd *
   3. No

 Esc to cancel · Tab to amend · ctrl+e to explain

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.77

Claude Code Version

2.1.112

Platform

Anthropic API

Operating System

Other Linux

Terminal/Shell

Other

Additional Information

_No response_