Add multilingual language and systems learning tracks

tl/vlang-foundations-20261101/lesson-3/main.v

@@ -0,0 +1,7 @@
+fn remaining(total int, done int) int {
+    if done >= total { return 0 }
+    return total - done
+}
+fn main() {
+    println(remaining(4, 1))
+}