Ensure that swe-rex version installed within container matches the one installed locally

[klieret]

If a user has an earlier version of the swe-rex "client" installed, we still pip install the most recent version of swe-rex on the remote/within the container. This version mismatch can then cause issues.

[rambip]

I would like to be sure I'm not mistaken about the following points:

1. The user always has to install swe-agent on his machine (or in a codespace) in order to use it
2. swe-agent has swe-rex as a direct dependency
3. when the local swe-agent runs a task locally, it will use one of the two lines of this file to install a containerized version of swe-rex (the latest release)
4. So they are always 2 potentially different versions of swe-rex, one outside and one inside the container.

If a user has an earlier version of the swe-rex "client" installed You mean for example that he pulled the repo some time ago, right ? Or I am missing something ?

Could you give some information about what part of the package is called externally and what part is called internally ? If you think it can cause strange behavior, I guess the 2 interact on some points.

Note: This kind of thing is quite hard to get right, see for example: https://github.com/wasm-bindgen/wasm-bindgen/issues/2619