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);
 }

Apis/cv-matcher-api/Services/JobTokenService.cs

@@ -63,7 +63,7 @@ public sealed class JobTokenService : IJobTokenService
     }
 
     /// <inheritdoc />
-    public async Task<string> TriggerStartAsync(string tokenId, CancellationToken ct)
+    public async Task<string> TriggerStartAsync(string tokenId, string? clientIpAddress, CancellationToken ct)
     {
         var token = await _db.JobSearchTokens.FirstOrDefaultAsync(x => x.Id == tokenId, ct);
         if (token is null) return StartJobSearchStatus.NotFound;
@@ -94,6 +94,7 @@ public sealed class JobTokenService : IJobTokenService
             Status = JobSearchStatus.Pending,
             Keywords = keywords,
             Location = token.Location,
+            ClientIpAddress = clientIpAddress,
             ProviderConfigJson = providerConfigJson,
             CreatedAt = DateTime.UtcNow
         };