CVE-2026-47425: rattler has an entry-point path traversal in noarch:python install (arbitrary file write)

EntryPoint::FromStr in rattler_conda_types performs only .trim() on the command field before the linker joins it onto the install prefix and writes an executable Python script. A malicious noarch:python package can ship an info/link.json with an entry-point name containing .., /, \, or an absolute path; the resulting file is written outside the prefix (or clobbers an existing in-prefix entry-point such as bin/pip) with mode 0o775 on Unix and a copied launcher .exe on Windows. This affects the default install path of pixi install, rattler-build, some methods in py-rattler, and any other consumer of the rattler install crate; no flag or post-link-script opt-in is involved.

Resolved in https://github.com/conda/rattler/pull/2445, released in rattler 0.43.2.