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/application/src/lib/projects.service.ts

@@ -1,3 +1,7 @@
+import {
+  ProposalKind,
+  SubmitProposalCommand,
+} from './commands/submit-proposal.command';
 import { GetShowcaseQuery, Showcase } from './queries/get-showcase.query';
 import { Injectable } from '@nestjs/common';
 import { CommandBus, QueryBus } from '@nestjs/cqrs';
@@ -34,6 +38,19 @@ export class ProjectsService {
   ) {}
 
   /** A public project's roadmap, releases, sprint and good first tickets (no token). */
+  /** A bug report or an idea from anyone, for a public project that takes them. */
+  propose(
+    project: string,
+    kind: ProposalKind,
+    title: string,
+    description: string,
+    author: string | null,
+  ): Promise<CommandResult> {
+    return this.commandBus.execute(
+      new SubmitProposalCommand(project, kind, title, description, author),
+    );
+  }
+
   showcase(project: string): Promise<Showcase> {
     return this.queryBus.execute(new GetShowcaseQuery(project));
   }
@@ -61,7 +78,12 @@ export class ProjectsService {
   update(
     actorId: string,
     projectId: string,
-    changes: { name?: string; description?: string | null; isPublic?: boolean },
+    changes: {
+      name?: string;
+      description?: string | null;
+      isPublic?: boolean;
+      acceptsProposals?: boolean;
+    },
   ): Promise<CommandResult> {
     return this.commandBus.execute(
       new UpdateProjectCommand(actorId, projectId, changes),