## Summary
After referring to https://github.com/astral-sh/uv/pull/5637 and doing
additional testing.
The default value in a stable state seems more reasonable to be
``only-system``. ``managed`` in preview.
```
cpython-3.11.9-windows-x86_64-none C:\Users\name\AppData\Local\Programs\Python\Python311\python.exe
cpython-3.10.14-windows-x86_64-none C:\Users\name\AppData\Roaming\uv\data\python\cpython-3.10.14-windows-x86_64-none\install\python.exe
cpython-3.10.11-windows-x86_64-none C:\Users\name\AppData\Local\Programs\Python\Python310\python.exe
cpython-3.9.19-windows-x86_64-none C:\Users\name\AppData\Roaming\uv\data\python\cpython-3.9.19-windows-x86_64-none\python.exe
```
test on uv 0.2.33 (build from
257007ccaf)
### Stable version
``uv venv -p 3.10`` is ``3.10.11`` (System Python)
``uv venv -p 3.9`` is ``No interpreter found``(3.9.19 for managed
Python)
``uv venv -p 3.9 --python-preference only-system`` is ``No interpreter
found``(fail)
``uv venv -p 3.9 --python-preference only-managed`` is
``3.9.19``(success)
Do not use managed Python, only use the system Python, so it can be
determined as ``only-system``.
### Preview mode
**Note:** ``3.10.14`` is managed python, ``3.10.11`` is system python.
``uv venv -p 3.11 --preview`` is ``3.11.9`` (System Python)
``uv venv -p 3.10 --preview`` is ``3.10.14``
``uv venv -p 3.10 --preview --python-preference only-managed`` is
``3.10.14``
``uv venv -p 3.10 --preview --python-preference managed`` is ``3.10.14``
``uv venv -p 3.10 --preview --python-preference system`` is ``3.10.11``
``venv -p 3.10 --preview --python-preference only-system`` is
``3.10.11``
Prioritize the managed Python and then select the system Python, so it
can be determined as ``managed``.
-----
fixed#5754
## Test Plan
Run website in local.
