feat: what is new since my last visit, and turning a comment into a ticket

Opening a ticket notes the visit and answers the one before (issue_visits),
so the page marks others' comments and changes since. A comment can become
a ticket of its own, as a subtask or linked; it remembers where it went.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libs/api/tracker/domain/src/lib/events/comment-turned-into-issue.event.ts

@@ -0,0 +1,17 @@
+import { AutowiredEvent } from '@task-stream/api/shared/domain';
+import { TrackerEvent } from './tracker.event';
+
+/** A ticket of its own was made from a comment («→ WEB-45» on it). */
+@AutowiredEvent
+export class CommentTurnedIntoIssueEvent extends TrackerEvent {
+  constructor(
+    actorId: string,
+    commentId: string,
+    projectId: string,
+    readonly issueId: string,
+    /** Every ticket made from it so far, this one last. */
+    readonly spawned: { id: string; key: string }[],
+  ) {
+    super(actorId, commentId, projectId);
+  }
+}

libs/api/tracker/domain/src/lib/events/index.ts

@@ -17,6 +17,7 @@ export * from './comment-edited.event';
 export * from './comment-reacted.event';
 export * from './comment-decision-marked.event';
 export * from './comment-thread-resolved.event';
+export * from './comment-turned-into-issue.event';
 export * from './issue-review.events';
 export * from './comment-poll.events';
 export * from './comment-deleted.event';