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/commands/attach-file.command-handler.ts

@@ -2,8 +2,8 @@ import { randomUUID } from 'node:crypto';
 import { CommandHandler, ICommandHandler } from '@nestjs/cqrs';
 import { BusinessRuleError } from '@task-stream/api/shared/domain';
 import { AttachmentStorage, attachmentKey } from '../ports/attachment-storage';
-import { AttachFileCommand } from './attach-file.command';
-import { CommandResult, ack } from './command-result';
+import { AttachFileCommand, AttachmentResult } from './attach-file.command';
+import { ack } from './command-result';
 import { WriteAccess } from './write-access';
 
 /**
@@ -19,7 +19,7 @@ export class AttachFileCommandHandler
     private readonly storage: AttachmentStorage,
   ) {}
 
-  async execute(command: AttachFileCommand): Promise<CommandResult> {
+  async execute(command: AttachFileCommand): Promise<AttachmentResult> {
     const { issue } = await this.access.issueForContributor(
       command.issueId,
       command.actorId,
@@ -52,6 +52,7 @@ export class AttachFileCommandHandler
       await this.storage.remove(key);
       throw error;
     }
-    return ack(issue);
+    // The id lets a client point at the file, e.g. an image inside a comment.
+    return { ...ack(issue), attachmentId: id };
   }
 }