fix(docker): set runtime user via compose to match host uid for volume access

[facorazza]

Run as the host user so mounted volumes (e.g. kiro-cli SQLite DB) are accessible. Since the kiro user in the image owns /app, this PR ensures the UID matches the host user who owns the files on mounted volumes

[cla-bot]

Thanks for the PR! 🎉

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[facorazza]

I have read the CLA and I don't accept its terms

[ankitcharolia]

@facorazza could you give a try to this gateway: https://github.com/ankitcharolia/kiro-gateway

It works quite well with All AI harness and actively being developed. The most important thing is that it is ACP compliant