Update with legacy API demo to say greetings

.vscode/settings.json

@@ -0,0 +1,5 @@
+{
+  "cSpell.words": [
+    "uniffi"
+  ]
+}

hello/platforms/HelloAppleDemoApp/Hello/Tests/HelloTests/HelloTests.swift

@@ -7,5 +7,6 @@ final class HelloTests: XCTestCase {
         // Use XCTAssert and related functions to verify your tests produce the correct
         // results.
 //      XCTAssertEqual(Hello.text, "Hello, World!")
+      XCTAssertEqual(rustGreeting(name: "Bob"), "Hello, Bob!")
     }
 }

hello/platforms/HelloAppleDemoApp/HelloAppleDemoApp/ViewController.swift

@@ -8,7 +8,7 @@ class ViewController: UIViewController {
   override func viewDidLoad() {
     super.viewDidLoad()
     // Do any additional setup after loading the view.
-    sayHello(name: "Apple Demo App")
+    print(rustGreeting(name: "Bob"))
   }
 }
 

hello/src/hello.udl

@@ -1,3 +1,3 @@
 namespace Hello {
-    void say_hello(string name);
+    string rust_greeting(string name);
 };

hello/src/lib.rs

@@ -1,6 +1,5 @@
-
-pub fn say_hello(name: String) {
-    println!("Hello, {}!", name);
+pub fn rust_greeting(to: String) -> String {
+    return format!("Hello, {}!", to);
 }
 
 include!(concat!(env!("OUT_DIR"), "/hello.uniffi.rs"));