Move models in separate projects

rag-api-models/Responses/IndexDocumentResponse.cs

@@ -0,0 +1,14 @@
+namespace Rag.Models.Responses
+{
+    public sealed class IndexDocumentResponse
+    {
+        public required string DocumentId { get; init; }
+        public required string TextHash { get; init; }
+        public required string DocumentType { get; init; }
+        public double DocumentTypeConfidence { get; init; }
+        public required string Title { get; init; }
+        public int Chunks { get; init; }
+        public int Characters { get; init; }
+        public bool Cached { get; init; }
+    }
+}