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/CvSearchDbContext.cs

@@ -51,6 +51,7 @@ public sealed class CvSearchDbContext : DbContext
             entity.Property(x => x.Keywords).HasMaxLength(1000);
             entity.Property(x => x.ProviderConfigJson).IsRequired(false);
             entity.Property(x => x.Language).HasMaxLength(8).HasDefaultValue("en").IsRequired();
+            entity.Property(x => x.ClientIpAddress).HasMaxLength(45);
             entity.Property(x => x.CreatedAt).HasDefaultValueSql("SYSUTCDATETIME()");
             entity.HasIndex(x => x.Status);
         });
@@ -64,6 +65,8 @@ public sealed class CvSearchDbContext : DbContext
             entity.Property(x => x.ProviderName).HasMaxLength(128);
             entity.Property(x => x.JobUrl).HasMaxLength(2048);
             entity.Property(x => x.JobTitle).HasMaxLength(512);
+            entity.Property(x => x.Email).HasMaxLength(256);
+            entity.Property(x => x.ClientIpAddress).HasMaxLength(45);
             entity.Property(x => x.CreatedAt).HasDefaultValueSql("SYSUTCDATETIME()");
             entity.HasIndex(x => x.SessionId);
         });