Added tool calling support (#731)

Co-authored-by: krut_ni <nils.kruthoff@dlr.de>
Co-authored-by: Thorsten Sommer <SommerEngineering@users.noreply.github.com>

app/MindWork AI Studio/Tools/ToolCallingSystem/ToolExecutionResult.cs

@@ -0,0 +1,24 @@
+using System.Text.Json.Nodes;
+
+using AIStudio.Provider;
+
+namespace AIStudio.Tools.ToolCallingSystem;
+
+public sealed class ToolExecutionResult
+{
+    public string? TextContent { get; init; }
+
+    public JsonNode? JsonContent { get; init; }
+
+    public IReadOnlyList<Source> Sources { get; init; } = [];
+
+    public ConfidenceLevel RequiredProviderConfidence { get; init; } = ConfidenceLevel.NONE;
+
+    public string ToModelContent()
+    {
+        if (this.JsonContent is not null)
+            return this.JsonContent.ToJsonString();
+
+        return this.TextContent ?? string.Empty;
+    }
+}