Talent lifecycle (21-day expiry) + noindex expired job/shift details

- Talent «آماده به کار» now has its own freshness window (21 days, vs 30
  for jobs) since availability goes stale fast; archiver, browse, and home
  use TalentCutoffUtc.
- Expired/filled job openings and past/filled shifts now emit
  robots noindex so Google drops dead listings instead of keeping
  soft-404 pages. (Talent details were already noindex.)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/JobsMedical.Web/Pages/Jobs/Details.cshtml

@@ -5,6 +5,8 @@
     var f = j.Facility!;
     ViewData["Title"] = j.Title;
     ViewData["Description"] = $"{j.Title} در {f.Name}، {f.City?.Name}. موقعیت استخدامی برای {j.Role?.Name}.";
+    // Don't let Google index filled/expired openings (avoids dead "Job for jobs" results).
+    if (j.Status != JobsMedical.Web.Models.ShiftStatus.Open) ViewData["NoIndex"] = true;
     string empLabel = j.EmploymentType switch
     {
         EmploymentType.FullTime => "تمام‌وقت",