Python packages not found if installed with venv

On mac os it works well with packages installed with `brew` but when using venv and packages installed with pip - it can't find it.

The `sys.path` is different when run with `python` and `bunpy`, the bunpy misses the venv installation dir

```
python

[
'/Users/alex/base/projects/ext_ts/math',
'/usr/local/Cellar/python@3.12/3.12.4/Frameworks/Python.framework/Versions/3.12/lib/python312.zip',
'/usr/local/Cellar/python@3.12/3.12.4/Frameworks/Python.framework/Versions/3.12/lib/python3.12',
'/usr/local/Cellar/python@3.12/3.12.4/Frameworks/Python.framework/Versions/3.12/lib/python3.12/lib-dynload',
'/Applications/misc/python/lib/python3.12/site-packages'
]

bunpy (misses '/Applications/misc/python/lib/python3.12/site-packages' )

[
'/usr/local/Cellar/python@3.12/3.12.4/Frameworks/Python.framework/Versions/3.12/lib/python312.zip',
'/usr/local/Cellar/python@3.12/3.12.4/Frameworks/Python.framework/Versions/3.12/lib/python3.12',
'/usr/local/Cellar/python@3.12/3.12.4/Frameworks/Python.framework/Versions/3.12/lib/python3.12/lib-dynload',
'/usr/local/Cellar/python@3.12/3.12.4/Frameworks/Python.framework/Versions/3.12/lib/python3.12/site-packages'
]
```

P.S.

I also had to explicitly set `python` lib, by default it can't find it

```
export DENO_PYTHON_PATH=/usr/local/Cellar/python@3.12/3.12.4/Frameworks/Python.framework/Versions/3.12/lib/libpython3.12.dylib
```

Inizia riproducendo il confronto tra gli entry point `python` e `bunpy` su macOS con una venv, registrando entrambi i valori di `sys.path` e l’effetto di `DENO_PYTHON_PATH`. Il lavoro è completato quando bunpy rileva i pacchetti installati e la libreria Python della venv senza perdere i percorsi mostrati dall’interprete normale.

Scritto dal modello di indicizzazione a partire dal testo della issue.