add vendoring

vendor/maunium.net/go/mautrix/util/gjson.go

@@ -0,0 +1,31 @@
+// Copyright (c) 2022 Tulir Asokan
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package util
+
+import (
+	"strings"
+)
+
+var GJSONEscaper = strings.NewReplacer(
+	`\`, `\\`,
+	".", `\.`,
+	"|", `\|`,
+	"#", `\#`,
+	"@", `\@`,
+	"*", `\*`,
+	"?", `\?`)
+
+func GJSONPath(path ...string) string {
+	var result strings.Builder
+	for i, part := range path {
+		_, _ = GJSONEscaper.WriteString(&result, part)
+		if i < len(path)-1 {
+			result.WriteRune('.')
+		}
+	}
+	return result.String()
+}