fix(cli): randomize sandbox container names

[Kkartik14]

The sequential -N allocator listed existing containers and picked the first unused index, which races when two CLIs start concurrently.

Replace it with a 12-hex random suffix using randomBytes(6), shared by the regular and integration-test branches. Drop the ps -a probe, and keep --name, --hostname, and SANDBOX aligned.

Fixes #12083

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a race condition in the CLI sandbox container allocation. By switching from a sequential index-based naming system to a randomized suffix approach, the CLI can now safely handle concurrent starts without attempting to reuse or conflict with existing container names. This change simplifies the container initialization process by removing the need to query the Docker daemon for existing containers before launching a new one.

Highlights

• Container Naming Strategy: Replaced the sequential container naming logic with a 12-hex random suffix generated via randomBytes(6) to prevent race conditions during concurrent CLI executions.
• Performance Improvement: Removed the 'ps -a' probe that checked for existing containers, reducing overhead and eliminating potential race conditions.
• Test Suite Updates: Updated sandbox tests to reflect the new random naming strategy and added verification for the removal of the 'ps -a' command.

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[gemini-code-assist]

Code Review

This pull request refactors the sandbox container naming logic to use a random 6-byte hex suffix instead of probing for sequential indices, preventing race conditions during concurrent CLI starts. The tests in packages/cli/src/utils/sandbox.test.ts were updated to mock node:crypto and verify the new naming behavior for both standard and integration test environments. I have no feedback to provide.

[SHARABUMANOJKUMAR]

Hi, I would like to work on this issue. I have been contributing to Gemini CLI and would love to take this up. Can I proceed?

[SHARABUMANOJKUMAR]

Hi, I would like to work on this issue. Can I proceed?

[Kkartik14]

Hey @jacob314 @cocosheng-g whenever you have time, since you were involved in the related issue, would appreciate any feedback on this PR. Happy to iterate on it!

[scidomino]

FYI, don't touch the PR or else we have to run the tests all over again.

[Kkartik14]

Yeah, I realized after updating, really appreciate you taking care of it, thanks!

[Kkartik14]

Hey @scidomino , the failing Windows checks don't look related to my changes, could you rerun them, or let me know if you'd like me to make any changes?

[Kkartik14]

Thanks for the review and merge