refactor: relocate options classes to dedicated Options folders

Move configuration options from Core/DataAccess/DataSync/ExcelIO to
dedicated Options folders within each project for better organization.
Update all references and tests accordingly.

NEW/src/JdeScoping.DataAccess/Options/SearchProcessingOptions.cs

@@ -0,0 +1,27 @@
+namespace JdeScoping.DataAccess.Options;
+
+/// <summary>
+/// Configuration options for search processing background service.
+/// </summary>
+public class SearchProcessingOptions
+{
+    /// <summary>
+    /// Configuration section name in appsettings.json.
+    /// </summary>
+    public const string SectionName = "SearchProcessing";
+
+    /// <summary>
+    /// Interval in seconds between polling for new search requests.
+    /// </summary>
+    public int PollingIntervalSeconds { get; set; } = 5;
+
+    /// <summary>
+    /// Maximum number of concurrent search operations.
+    /// </summary>
+    public int MaxConcurrentSearches { get; set; } = 2;
+
+    /// <summary>
+    /// Search operation timeout in minutes.
+    /// </summary>
+    public int SearchTimeoutMinutes { get; set; } = 30;
+}