refactor: updated folder structure

backend/sprik-backend/src/main/kotlin/Main.kt

@@ -0,0 +1,7 @@
+fun main(args: Array<String>) {
+    println("Hello World!")
+
+    // Try adding program arguments via Run/Debug configuration.
+    // Learn more about running applications: https://www.jetbrains.com/help/idea/running-applications.html.
+    println("Program arguments: ${args.joinToString()}")
+}