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-matcher-api/Services/Contracts/IJobTokenService.cs

@@ -25,10 +25,11 @@ public interface IJobTokenService
     /// Validates the token and, if valid, marks it as used and creates a <c>Pending</c> job search session.
     /// </summary>
     /// <param name="tokenId">The token ID from the one-click link.</param>
+    /// <param name="clientIpAddress">Client IP address forwarded by the api layer. Null when not available.</param>
     /// <param name="ct">Cancellation token.</param>
     /// <returns>
     /// One of the <c>StartJobSearchStatus</c> string constants:
     /// <c>Started</c>, <c>AlreadyUsed</c>, <c>Expired</c>, or <c>NotFound</c>.
     /// </returns>
-    Task<string> TriggerStartAsync(string tokenId, CancellationToken ct);
+    Task<string> TriggerStartAsync(string tokenId, string? clientIpAddress, CancellationToken ct);
 }