refactor: centralize message target resolution

Co-authored-by: Thinh Dinh <tobalsan@users.noreply.github.com>

extensions/msteams/src/channel.ts

@@ -133,6 +133,13 @@ export const msteamsPlugin: ChannelPlugin<ResolvedMSTeamsAccount> = {
   },
   messaging: {
     normalizeTarget: normalizeMSTeamsMessagingTarget,
+    looksLikeTargetId: (raw) => {
+      const trimmed = raw.trim();
+      if (!trimmed) return false;
+      if (/^(conversation:|user:)/i.test(trimmed)) return true;
+      return trimmed.includes("@thread");
+    },
+    targetHint: "<conversationId|user:ID|conversation:ID>",
   },
   directory: {
     self: async () => null,