Add medjobs.ir scraper + employer/employee choice at signup

- MedjobsListingSource: crawls medjobs.ir sitemaps (ad_listing-sitemapN) → fetches ad pages → title+description → engine (dedupe/parse/validate/publish as SEO job pages). Configured in /Admin/Settings (enable + max ads/run).
- Login/register now asks 'کادر درمان' vs 'کارفرما/مرکز': new accounts get Doctor vs FacilityAdmin role; post-login routes to /Me, /Employer, or /Admin accordingly.
- Verified live: medjobs run fetched real ads into the review queue; employer signup → /Employer.

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

src/JobsMedical.Web/Services/Scraping/SettingsService.cs

@@ -44,6 +44,8 @@ public class SettingsService
         s.DivarEnabled = incoming.DivarEnabled;
         s.DivarCity = string.IsNullOrWhiteSpace(incoming.DivarCity) ? "tehran" : incoming.DivarCity.Trim();
         s.DivarQueries = incoming.DivarQueries?.Trim();
+        s.MedjobsEnabled = incoming.MedjobsEnabled;
+        s.MedjobsMaxAds = Math.Clamp(incoming.MedjobsMaxAds, 1, 500);
         s.UpdatedAt = DateTime.UtcNow;
         await _db.SaveChangesAsync();
     }