Add copyright to .idea

.idea/copyright/Mamoe_mirai.xml

@@ -0,0 +1,7 @@
+<component name="CopyrightManager">
+  <copyright>
+    <option name="allowReplaceRegexp" value="2019\-2020" />
+    <option name="notice" value="Copyright 2019-2021 Mamoe Technologies and contributors.&#10;&#10; 此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.&#10; Use of this source code is governed by the GNU AGPLv3 license that can be found through the following link.&#10;&#10; https://github.com/mamoe/mirai/blob/master/LICENSE" />
+    <option name="myName" value="Mamoe/mirai" />
+  </copyright>
+</component>

.idea/copyright/profiles_settings.xml

@@ -0,0 +1,3 @@
+<component name="CopyrightManager">
+  <settings default="Mamoe/mirai" />
+</component>