feat: public projects, project deletion and sagas

Public projects:
- Project.isPublic (create/update, owners and admins). Anyone can read a
  public project without a token: project, board, tickets, comments,
  history, releases, activity, tracking and statistics, over GraphQL and
  REST. Writes stay for members (401 anonymous, 403 outsiders).
- @OptionalAuth() / @ApiOptionalPireonAuth(): anonymous callers allowed,
  invalid tokens still rejected. ReadAccess lets anonymous viewers read
  public projects only; linked tickets are filtered by visibility.
- publicProjects (GraphQL) and GET /api/explore/projects (REST).
- Web: «Explorar» page, project pages open without a session (read-only
  notice, sign-in hints), public badge, visibility switch in settings,
  no realtime subscriptions without a session.

Project deletion:
- Owner only, confirming the key (deleteProject / DELETE
  /api/projects/{project}?confirm=KEY). The key is freed; the read model
  drops the project and members are notified (web goes home).

Sagas (run by the EventsBridge after projections, durable and ordered):
- ProjectDeletionSaga: project deleted → delete its tickets and releases;
  ticket deleted → purge its comments and drop links from other tickets.
- ReleaseArchivedSaga: unfinished tickets leave an archived release.
- UserDeactivatedSaga: the Pireon webhook records UserDeactivatedEvent in
  the event store (EventRecorder); the tracker unassigns that user's open
  tickets as the system actor.
- Internal idempotent commands; domain refusals are logged and skipped,
  concurrency conflicts retried. Affected streams come from the event store
  (TrackerStreamsRepository).

Tests: domain lifecycle specs, saga specs run like the bridge, facade
tests, e2e for public access, cascade deletion, archived releases and
deactivation webhook. Docs, READMEs, schema.gql/openapi.json and Word/PDF
updated.

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

libs/api/tracker/application/src/lib/commands/command-handlers.ts

@@ -18,6 +18,13 @@ import { CreateReleaseCommandHandler } from './create-release.command-handler';
 import { UpdateReleaseCommandHandler } from './update-release.command-handler';
 import { PublishReleaseCommandHandler } from './publish-release.command-handler';
 import { ArchiveReleaseCommandHandler } from './archive-release.command-handler';
+import { DeleteProjectCommandHandler } from './delete-project.command-handler';
+import { DeleteIssueCommandHandler } from './delete-issue.command-handler';
+import { DeleteReleaseCommandHandler } from './delete-release.command-handler';
+import { PurgeCommentCommandHandler } from './purge-comment.command-handler';
+import { DropLinksToIssueCommandHandler } from './drop-links-to-issue.command-handler';
+import { DetachIssueFromReleaseCommandHandler } from './detach-issue-from-release.command-handler';
+import { UnassignIssueCommandHandler } from './unassign-issue.command-handler';
 
 export const COMMAND_HANDLERS = [
   CreateProjectCommandHandler,
@@ -40,4 +47,12 @@ export const COMMAND_HANDLERS = [
   UpdateReleaseCommandHandler,
   PublishReleaseCommandHandler,
   ArchiveReleaseCommandHandler,
+  DeleteProjectCommandHandler,
+  // Emitted by sagas only (cascades and reactions to other aggregates).
+  DeleteIssueCommandHandler,
+  DeleteReleaseCommandHandler,
+  PurgeCommentCommandHandler,
+  DropLinksToIssueCommandHandler,
+  DetachIssueFromReleaseCommandHandler,
+  UnassignIssueCommandHandler,
 ];