chore: add exception catch

src/main/kotlin/cn/rtast/fancybot/commands/lookup/NslookupCommand.kt

@@ -14,18 +14,24 @@ import cn.rtast.rob.util.ob.OneBotListener
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import java.net.InetAddress
+import java.net.UnknownHostException
 
 class NslookupCommand : BaseCommand() {
     override val commandNames = listOf("/nslookup", "/ns")
 
     override suspend fun executeGroup(listener: OneBotListener, message: GroupMessage, args: List<String>) {
+        val host = args.joinToString(" ")
+        try {
             val msg = MessageChain.Builder()
                 .addReply(message.messageId)
-            .addText("域名: ${args.first()}解析后的IP地址为: ")
-            .addText(withContext(Dispatchers.IO) {
-                InetAddress.getByName(args.first())
-            }.hostAddress)
+                .addText("域名: ${host}解析后的IP地址为: ")
+                .addText(withContext(Dispatchers.IO) { InetAddress.getByName(host) }.hostAddress)
                 .build()
             listener.sendGroupMessage(message.groupId, msg)
+        } catch (_: UnknownHostException) {
+            message.reply("未知的主机名: $host")
+        } catch (e: Exception) {
+            message.reply("未知错误: ${e.message}")
+        }
     }
 }

src/main/kotlin/cn/rtast/fancybot/commands/parse/AsciiArtCommand.kt

@@ -86,9 +86,7 @@ class AsciiArtCommand : BaseCommand() {
             if (message.sender.userId in waitingList) {
                 if (message.message.any { it.type == ArrayMessageType.image }) {
                     val url = message.message.find { it.type == ArrayMessageType.image }!!.data.file!!
-                    val bufferedImage = withContext(Dispatchers.IO) {
-                        ImageIO.read(URI(url).toURL())
-                    }
+                    val bufferedImage = withContext(Dispatchers.IO) { ImageIO.read(URI(url).toURL()) }
                     val imageBase64 =
                         bufferedImage.convertToAscii().saveAsciiArtToImage(bufferedImage.width, bufferedImage.height)
                     val msg = MessageChain.Builder().addImage(imageBase64, true).build()