Add Email and ClientIpAddress audit fields to cvSearch.JobSearchSessions and JobSearchResults

Captures client IP at job-search link-click time and threads it through to the session.
Both Email and ClientIpAddress are copied from session to each result row during processing.
Closes #47

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Apis/cv-search-data/Data/Entities/JobSearchSessionEntity.cs

@@ -10,6 +10,8 @@ public sealed class JobSearchSessionEntity : BaseEntity
     public string Status { get; set; } = JobSearchStatus.Pending;
     public string Keywords { get; set; } = string.Empty;
     public string? Location { get; set; }
+    /// <summary>Client IP address captured when the user clicked the one-time job-search link. Null for sessions created before this field was added.</summary>
+    public string? ClientIpAddress { get; set; }
     public string? ProviderConfigJson { get; set; }
     public string Language { get; set; } = "en";
 }