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/web/tracker/infrastructure/src/lib/adapters/graphql-collaboration.gateways.ts

@@ -25,6 +25,7 @@ import {
   ReactToCommentDocument,
   MarkDecisionDocument,
   ResolveThreadDocument,
+  TurnCommentIntoIssueDocument,
   VotePollDocument,
   ClosePollDocument,
   PublishReleaseDocument,
@@ -111,6 +112,22 @@ export class GraphqlCommentsGateway extends CommentsGateway {
       .pipe(map((d) => toCommandResult(d.resolveThread)));
   }
 
+  turnIntoIssue(
+    commentId: string,
+    title: string,
+    type: string,
+    asSubtask: boolean,
+  ): Observable<CommandResult> {
+    return this.gql
+      .mutate(TurnCommentIntoIssueDocument, {
+        commentId,
+        title,
+        type,
+        asSubtask,
+      })
+      .pipe(map((d) => toCommandResult(d.turnCommentIntoIssue)));
+  }
+
   markDecision(commentId: string, on: boolean): Observable<CommandResult> {
     return this.gql
       .mutate(MarkDecisionDocument, { commentId, on })