docs: add XML documentation and ConfigManager implementation plans

Add comprehensive XML documentation (param/returns tags) across 132 source
files to improve IntelliSense and API discoverability. Include ConfigManager
design documents and implementation plans for phases 1-9.

NEW/src/JdeScoping.DataSync/Etl/Scripts/SqlScriptRunner.cs

@@ -4,6 +4,9 @@ using JdeScoping.DataSync.Etl.Contracts;
 
 namespace JdeScoping.DataSync.Etl.Scripts;
 
+/// <summary>
+/// SQL script runner that executes SQL commands against the database.
+/// </summary>
 public class SqlScriptRunner : IScriptRunner
 {
     private readonly IDbConnectionFactory _connectionFactory;
@@ -11,8 +14,19 @@ public class SqlScriptRunner : IScriptRunner
     private readonly object? _parameters;
     private readonly int _timeoutSeconds;
 
+    /// <summary>
+    /// The name of this script.
+    /// </summary>
     public string ScriptName { get; }
 
+    /// <summary>
+    /// Initializes a new instance of the <see cref="SqlScriptRunner"/> class.
+    /// </summary>
+    /// <param name="connectionFactory">The database connection factory.</param>
+    /// <param name="sql">The SQL command to execute.</param>
+    /// <param name="name">The optional name of the script.</param>
+    /// <param name="parameters">The optional parameters for the SQL command.</param>
+    /// <param name="timeoutSeconds">The command timeout in seconds.</param>
     public SqlScriptRunner(
         IDbConnectionFactory connectionFactory,
         string sql,
@@ -30,6 +44,10 @@ public class SqlScriptRunner : IScriptRunner
         ScriptName = name ?? "SqlScript";
     }
 
+    /// <summary>
+    /// Executes the SQL script asynchronously.
+    /// </summary>
+    /// <param name="cancellationToken">The cancellation token.</param>
     public async Task ExecuteAsync(CancellationToken cancellationToken = default)
     {
         await using var connection = await _connectionFactory.CreateLotFinderConnectionAsync(cancellationToken);