Default aggregated ads to Job, not Shift (stop fabricating shift dates/times)

A generic hiring ad like «پرستار درمانگاه» was published as a dated SHIFT with an invented date
(«فردا») and default hours («۰۸:۰۰–۱۴:۰۰») the source never stated — because classification defaulted
to Shift. Now a dated Shift is only produced when the text carries an explicit shift signal
(شیفت/آنکال/کشیک/نوبت); everything else is an ongoing hiring post → Job (no date to invent). Fixed in
both the parser default and the Publish branch (so an AI mislabel can''t force a shift either).

ReclassifyMisclassifiedShiftsAsync (in the post-ingest auto-cleanup) converts the existing signal-less
aggregated shifts into jobs in place — copies the content to a JobOpening and archives the old shift
(its URL 410s). After one pass it''s a no-op since new ads no longer become shifts.

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

src/JobsMedical.Web/Services/ListingParser.cs

@@ -69,8 +69,11 @@ public class HeuristicListingParser : IListingParser
         }
         else
         {
-            p.Kind = (jobSignals && !shiftSignals) ? ListingKind.Job : ListingKind.Shift;
-            p.Notes.Add(p.Kind == ListingKind.Job ? "نوع: استخدام (تشخیص خودکار)" : "نوع: شیفت (تشخیص خودکار)");
+            // A dated SHIFT requires an explicit shift signal («شیفت/آنکال/کشیک/نوبت»). Otherwise the ad
+            // is an ongoing hiring post → Job. (Defaulting to Shift forced a fabricated date/time onto
+            // generic ads like «پرستار درمانگاه», which the source never stated.)
+            p.Kind = shiftSignals ? ListingKind.Shift : ListingKind.Job;
+            p.Notes.Add(p.Kind == ListingKind.Shift ? "نوع: شیفت (تشخیص خودکار)" : "نوع: استخدام (تشخیص خودکار)");
         }
 
         // --- Roles (an ad can name several at once: «پرستار سالمند و کودک و همراه بیمار») ---