can't use in devcontainer

[DawnMagnet]

Extension Version: latest

VS Code Version: latest

Browser Version:

Operating System: macOS 15

even I write a devcontainer.json like this, with port forwarding, and i can't get cph work inside devcontainer. it can open a sidebar page, but if i click the run button, it will stuck at state running

{
    "name": "cph-test",
    "image": "mcr.microsoft.com/devcontainers/base:bullseye",
    "features": {},
    "remoteEnv": {
        "LOCAL_WORKSPACE_FOLDER": "${localWorkspaceFolder}"
    },
    "customizations": {
        "vscode": {
            "extensions": [
                "DivyanshuAgrawal.competitive-programming-helper"
            ]
        }
    },
    "forwardPorts": [
        27121
    ]
}