feat: Begins implementing route definitions.

Sources/App/routes.swift

@@ -35,6 +35,10 @@ func routes(_ app: Application) throws {
     }
   }
 
+  app.get("health") { _ in
+    HTTPStatus.ok
+  }
+
   app.post("login") { req in
     @Dependency(\.database.users) var users
     let loginForm = try req.content.decode(User.Login.self)