fix(slack): fail closed on slash command channel type lookup

src/slack/monitor/slash.ts

@@ -34,6 +34,7 @@ import {
 } from "./allow-list.js";
 import { resolveSlackChannelConfig, type SlackChannelConfigResolved } from "./channel-config.js";
 import { buildSlackSlashCommandMatcher, resolveSlackSlashCommandConfig } from "./commands.js";
+import { normalizeSlackChannelType } from "./context.js";
 import { isSlackChannelAllowedByPolicy } from "./policy.js";
 import { deliverSlackSlashReplies } from "./replies.js";
 
@@ -176,8 +177,9 @@ export function registerSlackMonitorSlashCommands(params: {
       }
 
       const channelInfo = await ctx.resolveChannelName(command.channel_id);
-      const channelType =
+      const rawChannelType =
         channelInfo?.type ?? (command.channel_name === "directmessage" ? "im" : undefined);
+      const channelType = normalizeSlackChannelType(rawChannelType, command.channel_id);
       const isDirectMessage = channelType === "im";
       const isGroupDm = channelType === "mpim";
       const isRoom = channelType === "channel" || channelType === "group";