feat: implement ETL pipeline redesign and ConfigManager improvements

- Add pipeline registry with JSON-based configuration and hot-reload support
- Implement manual sync request feature with API, client UI, and database
- Improve ConfigManager: connection string dropdown in pipeline editor,
  step delete/reorder functionality, and fix JSON parsing for ConnectionStrings

NEW/src/JdeScoping.DataSync/Configuration/DestinationElement.cs

@@ -0,0 +1,22 @@
+namespace JdeScoping.DataSync.Configuration;
+
+/// <summary>
+/// Configuration for the pipeline destination.
+/// </summary>
+public class DestinationElement
+{
+    /// <summary>
+    /// Target table name in the cache database.
+    /// </summary>
+    public string Table { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Columns used to match existing records for upsert.
+    /// </summary>
+    public List<string> MatchColumns { get; set; } = [];
+
+    /// <summary>
+    /// Columns to exclude from UPDATE operations.
+    /// </summary>
+    public List<string> ExcludeFromUpdate { get; set; } = [];
+}

NEW/src/JdeScoping.DataSync/Configuration/EtlPipelineConfig.cs

@@ -0,0 +1,78 @@
+namespace JdeScoping.DataSync.Configuration;
+
+/// <summary>
+/// Represents an ETL pipeline definition loaded from a JSON file.
+/// </summary>
+public class EtlPipelineConfig
+{
+    /// <summary>
+    /// Unique name of the pipeline (must match filename, case-insensitive).
+    /// </summary>
+    public string Name { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Whether the pipeline is enabled for execution.
+    /// </summary>
+    public bool IsEnabled { get; set; } = true;
+
+    /// <summary>
+    /// If true, pipeline can only be triggered via ManualSyncRequest.
+    /// No interval validation is required for manual-only pipelines.
+    /// </summary>
+    public bool IsManualOnly { get; set; }
+
+    /// <summary>
+    /// Interval for mass sync in minutes. Null if mass sync not supported.
+    /// </summary>
+    public int? MassSyncIntervalMinutes { get; set; }
+
+    /// <summary>
+    /// Interval for daily sync in minutes. Null if daily sync not supported.
+    /// </summary>
+    public int? DailySyncIntervalMinutes { get; set; }
+
+    /// <summary>
+    /// Interval for hourly sync in minutes. Null if hourly sync not supported.
+    /// </summary>
+    public int? HourlySyncIntervalMinutes { get; set; }
+
+    /// <summary>
+    /// Scripts to run before the main sync. Optional.
+    /// </summary>
+    public List<ScriptElement> PreScripts { get; set; } = [];
+
+    /// <summary>
+    /// The data source configuration. Required.
+    /// </summary>
+    public SourceElement Source { get; set; } = null!;
+
+    /// <summary>
+    /// Data transformations to apply. Optional.
+    /// </summary>
+    public List<TransformElement> Transforms { get; set; } = [];
+
+    /// <summary>
+    /// The destination configuration. Required.
+    /// </summary>
+    public DestinationElement Destination { get; set; } = null!;
+
+    /// <summary>
+    /// Scripts to run after the main sync. Optional.
+    /// </summary>
+    public List<ScriptElement> PostScripts { get; set; } = [];
+
+    /// <summary>
+    /// Gets a value indicating whether the pipeline supports mass sync.
+    /// </summary>
+    public bool SupportsMassSync => MassSyncIntervalMinutes.HasValue;
+
+    /// <summary>
+    /// Gets a value indicating whether the pipeline supports daily sync.
+    /// </summary>
+    public bool SupportsDailySync => DailySyncIntervalMinutes.HasValue;
+
+    /// <summary>
+    /// Gets a value indicating whether the pipeline supports hourly sync.
+    /// </summary>
+    public bool SupportsHourlySync => HourlySyncIntervalMinutes.HasValue;
+}

NEW/src/JdeScoping.DataSync/Configuration/ParameterElement.cs

@@ -0,0 +1,27 @@
+namespace JdeScoping.DataSync.Configuration;
+
+/// <summary>
+/// Configuration for a query parameter.
+/// </summary>
+public class ParameterElement
+{
+    /// <summary>
+    /// Parameter name as used in query (e.g., ":dateUpdated").
+    /// </summary>
+    public string Name { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Format conversion (jdeJulian, jdeTime, etc.).
+    /// </summary>
+    public string? Format { get; set; }
+
+    /// <summary>
+    /// Source of the value (offset = from last sync time).
+    /// </summary>
+    public string Source { get; set; } = "offset";
+
+    /// <summary>
+    /// Static value if source is not offset.
+    /// </summary>
+    public string? Value { get; set; }
+}

NEW/src/JdeScoping.DataSync/Configuration/ScriptElement.cs

@@ -0,0 +1,17 @@
+namespace JdeScoping.DataSync.Configuration;
+
+/// <summary>
+/// Configuration for a pre/post script.
+/// </summary>
+public class ScriptElement
+{
+    /// <summary>
+    /// Connection identifier for script execution.
+    /// </summary>
+    public string Connection { get; set; } = "lotfinder";
+
+    /// <summary>
+    /// SQL script to execute.
+    /// </summary>
+    public string Script { get; set; } = string.Empty;
+}

NEW/src/JdeScoping.DataSync/Configuration/SourceElement.cs

@@ -0,0 +1,27 @@
+namespace JdeScoping.DataSync.Configuration;
+
+/// <summary>
+/// Configuration for the pipeline data source.
+/// </summary>
+public class SourceElement
+{
+    /// <summary>
+    /// Connection identifier (jde, cms, giw, lotfinder).
+    /// </summary>
+    public string Connection { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Query for incremental syncs (daily/hourly).
+    /// </summary>
+    public string Query { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Query for mass sync. Falls back to Query if not specified.
+    /// </summary>
+    public string? MassQuery { get; set; }
+
+    /// <summary>
+    /// Query parameters with format and source configuration.
+    /// </summary>
+    public Dictionary<string, ParameterElement> Parameters { get; set; } = new();
+}

NEW/src/JdeScoping.DataSync/Configuration/TransformElement.cs

@@ -0,0 +1,21 @@
+using System.Text.Json;
+
+namespace JdeScoping.DataSync.Configuration;
+
+/// <summary>
+/// Configuration for a data transformation.
+/// </summary>
+public class TransformElement
+{
+    /// <summary>
+    /// Type of transformation (ColumnDrop, ColumnRename, JdeDate, Regex, etc.).
+    /// </summary>
+    public string TransformType { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Transform-specific configuration as raw JSON.
+    /// Using JsonElement avoids Dictionary&lt;string, object&gt; deserialization issues
+    /// where values would become JsonElement anyway without custom converters.
+    /// </summary>
+    public JsonElement? Config { get; set; }
+}