fix: Suppress CA1873 at file level in SemanticKernelAgent sample (#306)

* Initial plan

* Fix CA1873: Replace LogInformation calls with [LoggerMessage] source-generated methods

Co-authored-by: rokonec <25249058+rokonec@users.noreply.github.com>

* Refactor: move [LoggerMessage] methods to dedicated internal Log class, remove partial from CurrencyPlugin and SemanticKernelTravelAgent

Co-authored-by: rokonec <25249058+rokonec@users.noreply.github.com>

* Simplify: replace Log partial class with file-level CA1873 pragma suppression

Co-authored-by: rokonec <25249058+rokonec@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: rokonec <25249058+rokonec@users.noreply.github.com>

Author: Copilot

samples/SemanticKernelAgent/SemanticKernelTravelAgent.cs

@@ -1,4 +1,5 @@
-using A2A;
+#pragma warning disable CA1873 // Avoid unnecessary lazy evaluation (coding sample — simplicity over micro-optimisation)
+using A2A;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Logging;
 using Microsoft.SemanticKernel;
@@ -53,8 +54,7 @@ public async Task<string> GetExchangeRateAsync(
     {
         try
         {
-            _logger.LogInformation("Getting exchange rate from {CurrencyFrom} to {CurrencyTo} for date {Date}",
-                currencyFrom, currencyTo, date);
+            _logger.LogInformation("Getting exchange rate from {CurrencyFrom} to {CurrencyTo} for date {Date}", currencyFrom, currencyTo, date);
 
             // Build request URL with query parameters
             var requestUri = $"https://api.frankfurter.app/{date}?from={Uri.EscapeDataString(currencyFrom)}&to={Uri.EscapeDataString(currencyTo)}";