Improve 'any' search message during uv python install

[zanieb]

Special cases the Any request in output

e.g.,

❯ cargo run -q -- python install --isolated
warning: `uv python install` is experimental and may change without warning.
Searching for Python installations
Found existing installation: cpython-3.12.3-macos-aarch64-none
Python is already available. Use `uv python install <request>` to install a specific version.

instead of

❯ cargo run -q -- python install --isolated
warning: `uv python install` is experimental and may change without warning.
Searching for Python versions matching: any Python
Found existing installation for any Python: cpython-3.12.3-macos-aarch64-none
Python is already available. Use `uv python install <request>` to install a specific version.

[zanieb]

Loosely considering keeping the existing messages when --verbose is used.