feat(template): add mobile projects, build script, fill initial src code (#305)

shared/template/ios/Sources/ExamplePlugin.swift

@@ -0,0 +1,16 @@
+import UIKit
+import WebKit
+import Tauri
+import SwiftRs
+
+class ExamplePlugin: Plugin {
+	@objc public func ping(_ invoke: Invoke) throws {
+		let value = invoke.getString("value")
+		invoke.resolve(["value": value as Any])
+	}
+}
+
+@_cdecl("init_plugin_{{ plugin_name_snake_case }}")
+func initPlugin(name: SRString, webview: WKWebView?) {
+	Tauri.registerPlugin(webview: webview, name: name.toString(), plugin: ExamplePlugin())
+}