Wireguard resolve strategy (#2717)

* 增加 wireguard 出站选项 `resolveStrategy`.

* They become a part of you.

* 移除不必要的选项别名.

* aliases NG.

* 微调.

---------

Co-authored-by: rui0572 <125641819+rui0572@users.noreply.github.com>

proxy/wireguard/config.go

@@ -0,0 +1,25 @@
+package wireguard
+
+func (c *DeviceConfig) preferIP4() bool {
+	return c.DomainStrategy == DeviceConfig_FORCE_IP ||
+		c.DomainStrategy == DeviceConfig_FORCE_IP4 ||
+		c.DomainStrategy == DeviceConfig_FORCE_IP46
+}
+
+func (c *DeviceConfig) preferIP6() bool {
+	return c.DomainStrategy == DeviceConfig_FORCE_IP ||
+		c.DomainStrategy == DeviceConfig_FORCE_IP6 ||
+		c.DomainStrategy == DeviceConfig_FORCE_IP64
+}
+
+func (c *DeviceConfig) hasFallback() bool {
+	return c.DomainStrategy == DeviceConfig_FORCE_IP46 || c.DomainStrategy == DeviceConfig_FORCE_IP64
+}
+
+func (c *DeviceConfig) fallbackIP4() bool {
+	return c.DomainStrategy == DeviceConfig_FORCE_IP64
+}
+
+func (c *DeviceConfig) fallbackIP6() bool {
+	return c.DomainStrategy == DeviceConfig_FORCE_IP46
+}