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/commands/vote-issue.command-handler.ts

@@ -24,6 +24,7 @@ export class VoteIssueCommandHandler
       throw new ForbiddenError(
         `You are not a member of project ${project.key}`,
       );
+    project.assertNotArchived();
     if (issue.trashedAt)
       throw new BusinessRuleError(`${issue.key} is in the trash`);
     issue.vote(command.actorId, command.on);