ACP & Canvas Cloud. Can someone 👀

launch pinned pre-installed CLI binary instead of npx

https://github.com/OpenHands/software-agent-sdk/pull/3490 I also had to fix some test isolation fix with DiscriminatedUnionMix

Actually this PR fix also this issue: https://github.com/OpenHands/software-agent-sdk/issues/3487 right? Cool, I will close my related PR 😉

applied suggestions + redoing e2e validations, will merge if green