Android Support (#166)

1. Add vpnservice tauri plugin for android.
2. add workflow for android.
3. Easytier Core support android, allow set tun fd.

tauri-plugin-vpnservice/src/models.rs

@@ -0,0 +1,33 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct PingRequest {
+    pub value: Option<String>,
+}
+
+#[derive(Debug, Clone, Default, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct PingResponse {
+    pub value: Option<String>,
+}
+
+#[derive(Debug, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct VoidRequest {}
+
+#[derive(Debug, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct StartVpnRequest {
+    pub ipv4_addr: Option<String>,
+    pub routes: Option<Vec<String>>,
+    pub dns: Option<String>,
+    pub disallowed_applications: Option<Vec<String>>,
+    pub mtu: Option<u32>,
+}
+
+#[derive(Debug, Clone, Default, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct Status {
+    pub error_msg: Option<String>,
+}