feat: add black list manager to manage group who kicked the bot

src/main/kotlin/cn/rtast/fancybot/util/misc/DateUtil.kt

@@ -9,10 +9,18 @@ package cn.rtast.fancybot.util.misc
 
 import java.time.Instant
 import java.time.ZoneId
+import java.time.format.DateTimeFormatter
+
+private val zoneId = ZoneId.of("Asia/Shanghai")
 
 fun Long.isSameDay(timestamp2: Long): Boolean {
-    val zoneId = ZoneId.of("Asia/Shanghai")
     val date1 = Instant.ofEpochSecond(this).atZone(zoneId).toLocalDate()
     val date2 = Instant.ofEpochSecond(timestamp2).atZone(zoneId).toLocalDate()
     return date1 == date2
 }
+
+fun Long.convertToDate(): String {
+    val instant = Instant.ofEpochSecond(this)
+    val formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd").withZone(zoneId)
+    return formatter.format(instant)
+}