feat: archive a project instead of deleting it

The owner archives a finished project (archiveProject, POST
/projects/{project}/archive) and brings it back (unarchive). While
archived it stays readable, managers still read its rules and webhooks,
but no command changes it: contributing and managing checks refuse with
422, votes and public proposals too, and automations do not run. The web
shows a read-only notice on every page of it (with «Desarchivar» for the
owner), hides what edits, marks it on the home page and lists it last.

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

libs/api/tracker/application/src/lib/event-handlers/event-handlers.ts

@@ -16,6 +16,7 @@ import { ProjectMemberAddedEventHandler } from './project-member-added.event-han
 import { ProjectMemberRemovedEventHandler } from './project-member-removed.event-handler';
 import { ProjectMemberRoleChangedEventHandler } from './project-member-role-changed.event-handler';
 import { ProjectUpdatedEventHandler } from './project-updated.event-handler';
+import { ProjectArchivedEventHandler } from './project-archived.event-handler';
 import { ReleaseArchivedEventHandler } from './release-archived.event-handler';
 import { ReleaseCreatedEventHandler } from './release-created.event-handler';
 import { ReleaseShippedEventHandler } from './release-shipped.event-handler';
@@ -63,6 +64,7 @@ export const EVENT_HANDLERS = [
   ProjectMemberRemovedEventHandler,
   ProjectMemberRoleChangedEventHandler,
   ProjectUpdatedEventHandler,
+  ProjectArchivedEventHandler,
   ProjectSettingsChangedEventHandler,
   ReleaseArchivedEventHandler,
   ReleaseCreatedEventHandler,