all: remove koka code, move go to repo root

skill_test.go

@@ -0,0 +1,31 @@
+package horse_test
+
+import (
+	"testing"
+
+	"git.sunturtle.xyz/zephyr/horse"
+)
+
+func TestTenThousandthsString(t *testing.T) {
+	t.Parallel()
+	cases := []struct {
+		val  horse.TenThousandths
+		want string
+	}{
+		{0, "0"},
+		{500, "0.05"},
+		{-500, "-0.05"},
+		{10000, "1"},
+		{-10000, "-1"},
+		{15000, "1.5"},
+		{-15000, "-1.5"},
+		{10001, "1.0001"},
+		{5000000, "500"},
+	}
+	for _, c := range cases {
+		got := c.val.String()
+		if got != c.want {
+			t.Errorf("%d: want %q, got %q", c.val, c.want, got)
+		}
+	}
+}