feat: quick polls in comments that end in a decision

«📊 Añadir una encuesta» adds 2 to 6 options to a new comment. Members,
viewers too, vote by clicking an option (one vote each, which they can
change or take back) and see each option's votes as a bar. Whoever
started it, or an admin, closes it with «Cerrar y decidir»: the most
voted wins (none on a tie) and a «Decidido: …» reply marked as a
decision shows above the ticket. Events of the comment (voted, closed).

API: addComment(…, poll), votePoll, closePoll, Comment.poll;
POST /api/comments/{id}/poll/vote and …/poll/close. MCP: add_comment
poll, vote_poll, close_poll.

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

libs/api/tracker/domain/src/lib/read-models/comment.read-model.ts

@@ -6,6 +6,14 @@ export class CommentReactionReadModel {
   users!: UserRefReadModel[];
 }
 
+/** A quick poll: each option with who voted it. */
+export class CommentPollReadModel {
+  options!: { text: string; voters: UserRefReadModel[] }[];
+  closed!: boolean;
+  /** Index of the winning option once closed (null on a tie). */
+  winner!: number | null;
+}
+
 export class CommentReadModel {
   id!: string;
   issueId!: string;
@@ -26,6 +34,8 @@ export class CommentReadModel {
   /** Who marked it and when (null when it is not a decision). */
   decidedBy!: UserRefReadModel | null;
   decidedAt!: string | null;
+  /** A quick poll in the comment, if any. */
+  poll!: CommentPollReadModel | null;
   /** A top-level comment whose conversation was settled. */
   resolved!: boolean;
   /** Who settled it and when (null while open). */