Added local RAG (#756)

Co-authored-by: Thorsten Sommer <SommerEngineering@users.noreply.github.com>

app/MindWork AI Studio/Settings/IInternalDataSource.cs

@@ -1,9 +1,27 @@
+using AIStudio.Provider;
+
 namespace AIStudio.Settings;
 
 public interface IInternalDataSource : IDataSource
 {
+    /// <summary>
+    /// Which provider confidence level is required by this internal data source?
+    /// </summary>
+    public ConfidenceLevel ConfidenceLevel { get; init; }
+
     /// <summary>
     /// The unique identifier of the embedding method used by this internal data source.
     /// </summary>
     public string EmbeddingId { get; init; }
+
+    /// <summary>
+    /// Optional maximum number of tokens per embedding chunk for this data source.
+    /// A value of 0 means the embedding provider's setting is used.
+    /// </summary>
+    public int MaxChunkTokenLength { get; init; }
+
+    /// <summary>
+    /// Optional number of tokens to overlap between consecutive chunks.
+    /// </summary>
+    public int ChunkOverlapTokenLength { get; init; }
 }