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/infrastructure/src/lib/mongo/find.repositories.ts

@@ -54,6 +54,7 @@ const commentFromDoc = (doc: CommentDoc): CommentReadModel => ({
   decision: doc.decision ?? false,
   decidedBy: doc.decidedBy ?? null,
   decidedAt: doc.decidedAt ?? null,
+  poll: doc.poll ?? null,
   resolved: doc.resolved ?? false,
   resolvedBy: doc.resolvedBy ?? null,
   resolvedAt: doc.resolvedAt ?? null,