Fix cross-device error when installing uv on Linux

[OskarAsplin]

Problem

On Linux systems where /tmp is mounted as tmpfs, installing the self-managed uv binary fails with:

OSError: [Errno 18] Invalid cross-device link: '/tmp/tmp.../uv' -> '~/.cache/.../lsp_utils/uv/uv'

This happens because Path.replace() calls os.rename() internally, which cannot move files across filesystem boundaries.

Fix

Pass dir=target_directory to TemporaryDirectory so temp files are created on the same filesystem as the destination, allowing os.rename() to succeed without any cross-device issue.