feat: formatted text, a list view, ticket details, public proposals and votes

Formatted text
- Descriptions, comments, replies and release notes render Markdown,
  sanitised with DOMPurify (tested against scripts, handlers and
  javascript: links). A pasted image is uploaded and written as
  ![name](attachment:<id>); the web fetches it with the reader's session,
  so it works on private projects. Every text box has a preview. The
  attachment upload now answers its attachmentId.

List view
- /p/:key/list: every ticket as rows, sortable by any column, filtered by
  text, open/closed, type, priority and assignee; status, priority and
  assignee change in place; bulk edit (the backlog's bar, now shared).

Ticket details
- Reactions on comments (GitHub's eight), for members and viewers.
- Duplicate a ticket: what it says, not where it stands.
- blockedBy: open tickets it waits for (BLOCKS / DEPENDS_ON), worked out
  when reading with one query per board or page; shown on cards, list
  rows and the ticket.

Public proposals
- A public project can take bug reports and ideas from anyone
  (acceptsProposals): POST /api/explore/projects/{project}/proposals and
  the form at /p/:key/proponer. They become tickets labelled «propuesta»,
  opened by TaskStream; a honeypot field and 5 per address every 15
  minutes keep spam out. No e-mail is asked: it would be public.

Votes
- Anyone signed in votes on a public project's tickets, members on a
  private one (voteIssue, PUT/DELETE /api/issues/{issue}/vote): votes and
  voted on each ticket, buttons on the ticket and the roadmap, a column
  in the list. The showcase carries votes and the open proposals.

MCP: vote_issue, duplicate_issue, react_to_comment; listings show
blockers and votes. Docs, Word and PDF updated; chat notifications
(Discord, Slack, Telegram) noted for later.

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

libs/api/tracker/domain/src/lib/comment/comment.ts

@@ -7,6 +7,10 @@ import {
 import { CommentAddedEvent } from '../events/comment-added.event';
 import { CommentDeletedEvent } from '../events/comment-deleted.event';
 import { CommentEditedEvent } from '../events/comment-edited.event';
+import { CommentReactedEvent } from '../events/comment-reacted.event';
+
+/** The reactions a comment takes, in the order they are shown (GitHub's). */
+export const REACTIONS = ['👍', '👎', '😄', '🎉', '😕', '❤️', '🚀', '👀'];
 
 /** Data of a comment (what CommentAddedEvent carries). */
 export interface CommentProps {
@@ -35,6 +39,8 @@ export class Comment extends VersionedAggregateRoot implements CommentProps {
   public authorId!: string;
   public body!: string;
   public replyTo: string | null = null;
+  /** Who chose each emoji (only the ones somebody chose). */
+  public reactions: Record<string, string[]> = {};
   public deleted = false;
   public createdAt!: string;
   public editedAt: string | null = null;
@@ -62,6 +68,31 @@ export class Comment extends VersionedAggregateRoot implements CommentProps {
     );
   }
 
+  /** Adds (`on`) or takes back the actor's reaction; repeating it changes nothing. */
+  react(actorId: string, emoji: string, on: boolean): void {
+    this.assertAlive();
+    assertThat(
+      REACTIONS.includes(emoji),
+      `Reactions are one of ${REACTIONS.join(' ')}`,
+    );
+    const users = this.reactions[emoji] ?? [];
+    if (on === users.includes(actorId)) return;
+    const next = {
+      ...this.reactions,
+      [emoji]: on ? [...users, actorId] : users.filter((u) => u !== actorId),
+    };
+    if (!next[emoji].length) delete next[emoji];
+    this.apply(
+      new CommentReactedEvent(
+        actorId,
+        this.id,
+        this.projectId,
+        this.issueId,
+        next,
+      ),
+    );
+  }
+
   /** @param canModerate whether the actor manages the project (may delete others' comments). */
   delete(actorId: string, canModerate: boolean): void {
     this.assertAlive();
@@ -86,6 +117,10 @@ export class Comment extends VersionedAggregateRoot implements CommentProps {
     this.editedAt = event.occurredAt;
   }
 
+  onCommentReactedEvent(event: CommentReactedEvent): void {
+    this.reactions = event.reactions;
+  }
+
   onCommentDeletedEvent(): void {
     this.deleted = true;
   }