chore(constants): internal/constants/providers

- New package to avoid package import cycles

internal/constants/providers/providers.go

@@ -0,0 +1,53 @@
+package providers
+
+const (
+	// Custom is the VPN provider name for custom
+	// VPN configurations.
+	Custom                = "custom"
+	Cyberghost            = "cyberghost"
+	Expressvpn            = "expressvpn"
+	Fastestvpn            = "fastestvpn"
+	HideMyAss             = "hidemyass"
+	Ipvanish              = "ipvanish"
+	Ivpn                  = "ivpn"
+	Mullvad               = "mullvad"
+	Nordvpn               = "nordvpn"
+	Perfectprivacy        = "perfect privacy"
+	Privado               = "privado"
+	PrivateInternetAccess = "private internet access"
+	Privatevpn            = "privatevpn"
+	Protonvpn             = "protonvpn"
+	Purevpn               = "purevpn"
+	Surfshark             = "surfshark"
+	Torguard              = "torguard"
+	VPNUnlimited          = "vpn unlimited"
+	Vyprvpn               = "vyprvpn"
+	Wevpn                 = "wevpn"
+	Windscribe            = "windscribe"
+)
+
+func All() []string {
+	return []string{
+		Custom,
+		Cyberghost,
+		Expressvpn,
+		Fastestvpn,
+		HideMyAss,
+		Ipvanish,
+		Ivpn,
+		Mullvad,
+		Nordvpn,
+		Perfectprivacy,
+		Privado,
+		PrivateInternetAccess,
+		Privatevpn,
+		Protonvpn,
+		Purevpn,
+		Surfshark,
+		Torguard,
+		VPNUnlimited,
+		Vyprvpn,
+		Wevpn,
+		Windscribe,
+	}
+}