Improve "embeddings" example (#525)

* Embeddings example: set EmbeddingMode true

prevents an exception from being thrown when GetEmbeddings() is called

* Embeddings example: improve documentation and styling

* docs: improve GetEmbeddings page

If EmbeddingMode is not set to true, GetEmbeddings() throws an exception

* docs: improve GetEmbeddings page

The previous commit 6c9ff3158c was inaccurate

* Embeddings example: improve styling

displays the example description after the model is loaded to ensure the text is on the screen at the time the prompt is first requested

LLama.Examples/Examples/GetEmbeddings.cs

@@ -6,21 +6,38 @@ namespace LLama.Examples.Examples
     {
         public static void Run()
         {
+            Console.ForegroundColor = ConsoleColor.White;
             Console.Write("Please input your model path: ");
             var modelPath = Console.ReadLine();
 
-            var @params = new ModelParams(modelPath);
+            Console.ForegroundColor = ConsoleColor.DarkGray;
+            var @params = new ModelParams(modelPath) { EmbeddingMode = true };
             using var weights = LLamaWeights.LoadFromFile(@params);
             var embedder = new LLamaEmbedder(weights, @params);
 
+            Console.ForegroundColor = ConsoleColor.Yellow;
+            Console.WriteLine(
+                """
+                This example displays embeddings from a text prompt.
+                Embeddings are numerical codes that represent information like words, images, or concepts.
+                These codes capture important relationships between those objects, 
+                like how similar words are in meaning or how close images are visually.
+                This allows machine learning models to efficiently understand and process complex data.
+                Embeddings of a text in LLM is sometimes useful, for example, to train other MLP models.
+                """); // NOTE: this description was AI generated
+
             while (true)
             {
+                Console.ForegroundColor = ConsoleColor.White;
                 Console.Write("Please input your text: ");
                 Console.ForegroundColor = ConsoleColor.Green;
                 var text = Console.ReadLine();
                 Console.ForegroundColor = ConsoleColor.White;
 
-                Console.WriteLine(string.Join(", ", embedder.GetEmbeddings(text)));
+                float[] embeddings = embedder.GetEmbeddings(text).Result;
+                Console.WriteLine($"Embeddings contain {embeddings.Length:N0} floating point values:");
+                Console.ForegroundColor = ConsoleColor.DarkGray;
+                Console.WriteLine(string.Join(", ", embeddings.Take(20)) + ", ...");
                 Console.WriteLine();
             }
         }

docs/Examples/GetEmbeddings.md

@@ -14,7 +14,8 @@ public class GetEmbeddings
     {
         Console.Write("Please input your model path: ");
         string modelPath = Console.ReadLine();
-        var embedder = new LLamaEmbedder(new ModelParams(modelPath));
+        var modelParams = new ModelParams(modelPath) { EmbeddingMode = true };
+        var embedder = new LLamaEmbedder(modelParams);
 
         while (true)
         {