Support operator in `GroupNameChangeEvent`, optimize logs, close #217

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/contact/GroupImpl.kt

@@ -120,7 +120,7 @@ internal class GroupImpl(
                             newName = newValue
                         ).sendWithoutExpect()
                     }
-                    GroupNameChangeEvent(oldValue, newValue, this@GroupImpl, true).broadcast()
+                    GroupNameChangeEvent(oldValue, newValue, this@GroupImpl, null).broadcast()
                 }
             }
         }

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/BotEvents.kt

@@ -301,8 +301,16 @@ data class GroupNameChangeEvent(
     override val origin: String,
     override val new: String,
     override val group: Group,
-    val isByBot: Boolean // 无法获取操作人
-) : GroupSettingChangeEvent<String>, Packet
+    /**
+     * 操作人. 为 null 时则是机器人操作
+     */
+    @SinceMirai("0.37.3")
+    override val operator: Member?
+) : GroupSettingChangeEvent<String>, Packet, GroupOperableEvent {
+    @Deprecated("for binary compatibility", level = DeprecationLevel.HIDDEN)
+    val isByBot: Boolean
+        get() = operator == null
+}
 
 /**
  * 入群公告改变. 此事件广播前修改就已经完成.

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/types.kt

@@ -67,7 +67,10 @@ interface GroupOperableEvent : GroupEvent {
 /**
  * 是否由 [Bot] 操作
  */
-val GroupOperableEvent.isByBot: Boolean get() = operator == null
+@Suppress("INVISIBLE_REFERENCE", "INVISIBLE_MEMBER")
+@kotlin.internal.HidesMembers // necessary until 1.0.0
+val GroupOperableEvent.isByBot: Boolean
+    get() = operator == null
 
 /**
  * 当操作人为 [Member] 时获取这个 [Member],