Add iranestekhdam.ir as an ingestion source (clinical job ads at named facilities)

New IranEstekhdamListingSource: reads the site monthly ad sitemaps
(sitemap-ads.xml -> sitemap-ads-YYYY-M.xml), keeps only ad URLs whose Persian slug names a
clinical role (veterinary/non-clinical excluded), then extracts each ad title + description
(+ phone). These are employer ads at NAMED facilities, so they directly improve the
unknown-facility problem the classifieds content has.

Wired in like Medjobs: AppSetting toggles (IranEstekhdamEnabled/MaxAds/UseProxy) + EF
migration, SettingsService persistence, admin Settings UI, and DI registration. Off by
default; the medical-gate validator + AI auditor + junk filters screen results downstream.

Note: e-estekhdam / jobinja / jobvision are JS-rendered SPAs whose ad lists are not in static
HTML, so they need API reverse-engineering (a separate effort), not this static-scrape path.

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

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

@@ -55,6 +55,9 @@ public class SettingsService
         s.DivarQueries = incoming.DivarQueries?.Trim();
         s.MedjobsEnabled = incoming.MedjobsEnabled;
         s.MedjobsMaxAds = Math.Clamp(incoming.MedjobsMaxAds, 1, 500);
+        s.IranEstekhdamEnabled = incoming.IranEstekhdamEnabled;
+        s.IranEstekhdamMaxAds = Math.Clamp(incoming.IranEstekhdamMaxAds, 1, 500);
+        s.IranEstekhdamUseProxy = incoming.IranEstekhdamUseProxy;
         s.SmsEnabled = incoming.SmsEnabled;
         s.SmsApiKey = incoming.SmsApiKey?.Trim();
         s.SmsTemplate = incoming.SmsTemplate?.Trim();