Feature request: Protonvpn filtering by features

[qdm12]

What's the feature 🧐

Each server JSON object from their API has a feature number corresponding to a feature detailed in https://github.com/ProtonVPN/protonvpn-nm-lib/blob/31d5f99fbc89274e4e977a11e7432c0eab5a3ef8/protonvpn_nm_lib/enums.py#L44-L49

Gluetun should allow to filter servers by feature

Extra information and references

No response

[ProfDoof]

What needs to be done to support this? I'd be willing to take a brief crack at it here in the next couple of weeks but don't know where you would want me to start.

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