feat(utils): add pkg utils

pkg/sliceutils/sliceutils.go

@@ -0,0 +1,17 @@
+package sliceutils
+
+func First[T any](s []T) (T, bool) {
+	if len(s) == 0 {
+		var zeroT T
+		return zeroT, false
+	}
+	return s[0], true
+}
+
+func Map[R, I any](s []I, f func(I) R) []R {
+	r := make([]R, 0, len(s))
+	for _, v := range s {
+		r = append(r, f(v))
+	}
+	return r
+}