docs: add installation prerequisites and quickstart guide to README

tests/oop_step1.rc

@@ -0,0 +1,11 @@
+class Empty {
+    int value = 42;
+}
+
+int main() {
+    printf("Step 1: Object creation test\n");
+    int obj = new Empty();
+    printf("Object created, pointer = %d\n", obj);
+    printf("Success!\n");
+    return 0;
+}