fix: Prevent Linear unfurl errors from bubbling to error tracking (#12532)

Returning the unfurl promises without awaiting them inside the try
block meant rejections (e.g. "Entity not found: Issue") escaped the
catch and were reported to error tracking. Await them so they are
caught and returned as a handled { error } result.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

plugins/linear/server/linear.ts

@@ -148,9 +148,9 @@ export class Linear {
 
       switch (resource.type) {
         case UnfurlResourceType.Issue:
-          return Linear.unfurlIssue(client, resource.id, actor);
+          return await Linear.unfurlIssue(client, resource.id, actor);
         case UnfurlResourceType.Project:
-          return Linear.unfurlProject(client, resource.id, actor);
+          return await Linear.unfurlProject(client, resource.id, actor);
         default:
           return;
       }