feat(protonvpn): feature filters (#2182)

- `SECURE_CORE_ONLY`
- `TOR_ONLY`
- `P2P_ONLY`

internal/provider/protonvpn/updater/servers.go

@@ -37,6 +37,18 @@ func (u *Updater) FetchServers(ctx context.Context, minServers int) (
 		// TODO v4 remove `name` field because of
 		// https://github.com/qdm12/gluetun/issues/1018#issuecomment-1151750179
 		name := logicalServer.Name
+
+		//nolint:lll
+		// See https://github.com/ProtonVPN/protonvpn-nm-lib/blob/31d5f99fbc89274e4e977a11e7432c0eab5a3ef8/protonvpn_nm_lib/enums.py#L44-L49
+		featuresBits := logicalServer.Features
+		features := features{
+			secureCore: featuresBits&1 != 0,
+			tor:        featuresBits&2 != 0,
+			p2p:        featuresBits&4 != 0,
+			stream:     featuresBits&8 != 0,
+			// ipv6: featuresBits&16 != 0, - unused.
+		}
+
 		for _, physicalServer := range logicalServer.Servers {
 			if physicalServer.Status == 0 { // disabled so skip server
 				u.warner.Warn("ignoring server " + physicalServer.Domain + " with status 0")
@@ -60,7 +72,7 @@ func (u *Updater) FetchServers(ctx context.Context, minServers int) (
 				u.warner.Warn(warning)
 			}
 
-			ipToServer.add(country, region, city, name, hostname, free, entryIP)
+			ipToServer.add(country, region, city, name, hostname, free, entryIP, features)
 		}
 	}