Feature Request: Allow disabling or intercepting bash mode (! prefix) commands

Problem

The ! prefix (bash mode) allows users to run shell commands directly without going through Claude's permission system or hooks. This creates a security gap for organizations using a multi-user security architecture.

Current Behavior

1. User types ! cat /secure/file.txt
2. Command executes directly in the shell
3. No hooks fire (PreToolUse, PostToolUse, etc.)
4. No permission rules apply
5. User bypasses all security controls

Verified Testing

We added a PreToolUse hook with matcher: "Bash" that logs all invocations:

{
  "hooks": {
    "PreToolUse": [
      {
        "matcher": "Bash",
        "hooks": [
          {
            "type": "command",
            "command": "/path/to/hook.sh"
          }
        ]
      }
    ]
  }
}

Result: The hook fires for normal Bash tool usage but never fires for ! commands.

Use Case

We have a two-user security architecture:

• dev user: Regular development work
• exo user: Access to secure organizational resources

Claude Code runs as exo user to access secure resources through controlled tool calls. However, the ! prefix allows users to directly access anything the exo user can access, bypassing our security model.

Requested Solutions (any of these would help)

1. Setting to disable bash mode entirely: "disableBashMode": true
2. Hook support for bash mode: Make PreToolUse/PostToolUse fire for ! commands
3. Permission rule for bash mode: Allow deny: ["BashMode"] or similar
4. Managed settings support: Allow operators to disable bash mode organization-wide

Environment

• Claude Code version: v2.1.4+
• Platform: Linux (Docker container)
• Using: Hooks, custom permissions, multi-user setup