Missing pv.netcdf - #343

@peterdudfield could you review this when you have time?

@peterdudfield this is ready to merge?

Hye, Would you be able to get unit tests working? Or is that something else?

Test: tests/unit/api_tests/v0/test_api.py::test_api_ok

Root error:

NameError: name 'RequestsCookieJar' is not defined

Where it happens:
Deep in requests_cache's cattrs serializer, when trying to cache an HTTP response from the Open-Meteo weather API.

The chain:

1. Test calls POST /forecast/
2. API calls get_nwp() → hits Open-Meteo via openmeteo-requests
3. openmeteo-requests uses requests-cache 1.2.0 to cache the response
4. requests-cache uses cattrs to serialize the response
5. cattrs 26.1.0 tries to resolve type hints on a requests internal class
6. requests 2.34.2 uses a forward reference 'RequestsCookieJar' in its type annotations
7. cattrs can't resolve that forward reference → NameError

• Downgrading cattrs to 23.2.3 didn't help — same error persists
• Downgrading requests to 2.31.0 was suggested but the venv has other packages (scipy, xgboost) compiled against newer numpy/requests ABIs, causing binary incompatibilities
• The project's pyproject.toml doesn't pin cattrs or requests at all, so any fresh install pulls incompatible versions

@peterdudfield have a look