hakurei: move container helpers toplevel

Signed-off-by: Ophestra <cat@gensokyo.uk>

sandbox/vfs/mangle_test.go

@@ -1,27 +0,0 @@
-package vfs_test
-
-import (
-	"testing"
-
-	"git.gensokyo.uk/security/hakurei/sandbox/vfs"
-)
-
-func TestUnmangle(t *testing.T) {
-	testCases := []struct {
-		want   string
-		sample string
-	}{
-		{`\, `, `\134\054\040`},
-		{`(10) source -- maybe empty string`, `(10)\040source\040--\040maybe empty string`},
-	}
-
-	for _, tc := range testCases {
-		t.Run(tc.want, func(t *testing.T) {
-			got := vfs.Unmangle(tc.sample)
-			if got != tc.want {
-				t.Errorf("Unmangle: %q, want %q",
-					got, tc.want)
-			}
-		})
-	}
-}