Skip unverified institution flag for unknown institutions

Filter out empty, "Unknown", and "Unknown Institution" values
from generating verification flags since there's nothing to verify.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/TrueCV.Infrastructure/Jobs/ProcessCVCheckJob.cs

@@ -385,7 +385,11 @@ public sealed class ProcessCVCheckJob
         }
 
         // Penalty for unverified education (not recognised, but not flagged as fake)
-        foreach (var edu in educationResults.Where(e => !e.IsVerified && !e.IsDiplomaMill && !e.IsSuspicious && e.Status == "Unknown"))
+        // Skip unknown/empty institutions as there's nothing to verify
+        foreach (var edu in educationResults.Where(e => !e.IsVerified && !e.IsDiplomaMill && !e.IsSuspicious && e.Status == "Unknown"
+            && !string.IsNullOrWhiteSpace(e.ClaimedInstitution)
+            && !e.ClaimedInstitution.Equals("Unknown Institution", StringComparison.OrdinalIgnoreCase)
+            && !e.ClaimedInstitution.Equals("Unknown", StringComparison.OrdinalIgnoreCase)))
         {
             score -= UnverifiedEducationPenalty;