.Net: Updated OpenTelemetry GenAI attributes (#11630)

### Motivation and Context

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Updated OpenTelemetry GenAI attributes to the latest version:
https://opentelemetry.io/docs/specs/semconv/gen-ai/gen-ai-spans/

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

Author: dmytrostruk

dotnet/src/Connectors/Connectors.Amazon/Bedrock/Core/Clients/BedrockChatCompletionClient.cs

@@ -76,8 +76,8 @@ internal async Task<IReadOnlyList<ChatMessageContent>> GenerateChatMessageAsync(
             {
                 activityStatus = BedrockClientUtilities.ConvertHttpStatusCodeToActivityStatusCode(response.HttpStatusCode);
                 activity.SetStatus(activityStatus);
-                activity.SetPromptTokenUsage(response?.Usage?.InputTokens ?? default);
-                activity.SetCompletionTokenUsage(response?.Usage?.OutputTokens ?? default);
+                activity.SetInputTokensUsage(response?.Usage?.InputTokens ?? default);
+                activity.SetOutputTokensUsage(response?.Usage?.OutputTokens ?? default);
             }
         }
         catch (Exception ex)
@@ -90,8 +90,8 @@ internal async Task<IReadOnlyList<ChatMessageContent>> GenerateChatMessageAsync(
                 {
                     activityStatus = BedrockClientUtilities.ConvertHttpStatusCodeToActivityStatusCode(response.HttpStatusCode);
                     activity.SetStatus(activityStatus);
-                    activity.SetPromptTokenUsage(response?.Usage?.InputTokens ?? default);
-                    activity.SetCompletionTokenUsage(response?.Usage?.OutputTokens ?? default);
+                    activity.SetInputTokensUsage(response?.Usage?.InputTokens ?? default);
+                    activity.SetOutputTokensUsage(response?.Usage?.OutputTokens ?? default);
                 }
                 else
                 {

dotnet/src/Connectors/Connectors.MistralAI/Client/MistralClient.cs

@@ -89,11 +89,11 @@ internal async Task<IReadOnlyList<ChatMessageContent>> GetChatMessageContentsAsy
                         {
                             if (usage.PromptTokens is int promptTokens)
                             {
-                                activity.SetPromptTokenUsage(promptTokens);
+                                activity.SetInputTokensUsage(promptTokens);
                             }
                             if (usage.CompletionTokens is int completionTokens)
                             {
-                                activity.SetCompletionTokenUsage(completionTokens);
+                                activity.SetOutputTokensUsage(completionTokens);
                             }
                         }
                     }

dotnet/src/Connectors/Connectors.OpenAI/Core/ClientCore.ChatCompletion.cs

@@ -180,8 +180,8 @@ internal async Task<IReadOnlyList<ChatMessageContent>> GetChatMessageContentsAsy
                         // Capture available metadata even if the operation failed.
                         activity
                             .SetResponseId(chatCompletion.Id)
-                            .SetPromptTokenUsage(chatCompletion.Usage.InputTokenCount)
-                            .SetCompletionTokenUsage(chatCompletion.Usage.OutputTokenCount);
+                            .SetInputTokensUsage(chatCompletion.Usage.InputTokenCount)
+                            .SetOutputTokensUsage(chatCompletion.Usage.OutputTokenCount);
                     }
 
                     throw;

dotnet/src/InternalUtilities/src/Diagnostics/ModelDiagnostics.cs

@@ -133,20 +133,20 @@ internal static void EndStreaming(
     internal static Activity SetResponseId(this Activity activity, string responseId) => activity.SetTag(ModelDiagnosticsTags.ResponseId, responseId);
 
     /// <summary>
-    /// Set the prompt token usage for a given activity.
+    /// Set the input tokens usage for a given activity.
     /// </summary>
-    /// <param name="activity">The activity to set the prompt token usage</param>
-    /// <param name="promptTokens">The number of prompt tokens used</param>
-    /// <returns>The activity with the prompt token usage set for chaining</returns>
-    internal static Activity SetPromptTokenUsage(this Activity activity, int promptTokens) => activity.SetTag(ModelDiagnosticsTags.PromptToken, promptTokens);
+    /// <param name="activity">The activity to set the input tokens usage</param>
+    /// <param name="inputTokens">The number of input tokens used</param>
+    /// <returns>The activity with the input tokens usage set for chaining</returns>
+    internal static Activity SetInputTokensUsage(this Activity activity, int inputTokens) => activity.SetTag(ModelDiagnosticsTags.InputTokens, inputTokens);
 
     /// <summary>
-    /// Set the completion token usage for a given activity.
+    /// Set the output tokens usage for a given activity.
     /// </summary>
-    /// <param name="activity">The activity to set the completion token usage</param>
-    /// <param name="completionTokens">The number of completion tokens used</param>
-    /// <returns>The activity with the completion token usage set for chaining</returns>
-    internal static Activity SetCompletionTokenUsage(this Activity activity, int completionTokens) => activity.SetTag(ModelDiagnosticsTags.CompletionToken, completionTokens);
+    /// <param name="activity">The activity to set the output tokens usage</param>
+    /// <param name="outputTokens">The number of output tokens used</param>
+    /// <returns>The activity with the output tokens usage set for chaining</returns>
+    internal static Activity SetOutputTokensUsage(this Activity activity, int outputTokens) => activity.SetTag(ModelDiagnosticsTags.OutputTokens, outputTokens);
 
     /// <summary>
     /// Check if model diagnostics is enabled
@@ -316,23 +316,23 @@ private static void ToOpenAIFormat(StringBuilder sb, ChatMessageContentItemColle
     private static void SetCompletionResponse<T>(
         Activity activity,
         T completions,
-        int? promptTokens,
-        int? completionTokens,
+        int? inputTokens,
+        int? outputTokens,
         Func<T, string> formatCompletions) where T : IEnumerable<KernelContent>
     {
         if (!IsModelDiagnosticsEnabled())
         {
             return;
         }
 
-        if (promptTokens != null)
+        if (inputTokens != null)
         {
-            activity.SetTag(ModelDiagnosticsTags.PromptToken, promptTokens);
+            activity.SetTag(ModelDiagnosticsTags.InputTokens, inputTokens);
         }
 
-        if (completionTokens != null)
+        if (outputTokens != null)
         {
-            activity.SetTag(ModelDiagnosticsTags.CompletionToken, completionTokens);
+            activity.SetTag(ModelDiagnosticsTags.OutputTokens, outputTokens);
         }
 
         activity
@@ -409,7 +409,8 @@ private static Activity SetFinishReasons(this Activity activity, IEnumerable<Ker
 
         if (finishReasons.Any())
         {
-            activity.SetTag(ModelDiagnosticsTags.FinishReason, $"{string.Join(",", finishReasons)}");
+            activity.SetTag(ModelDiagnosticsTags.FinishReason, $"[{string.Join(",",
+                finishReasons.Select(finishReason => $"\"{finishReason}\""))}]");
         }
 
         return activity;
@@ -466,10 +467,8 @@ private static class ModelDiagnosticsTags
         public const string ResponseId = "gen_ai.response.id";
         public const string ResponseModel = "gen_ai.response.model";
         public const string FinishReason = "gen_ai.response.finish_reason";
-        public const string PromptToken = "gen_ai.response.prompt_tokens";
-        public const string CompletionToken = "gen_ai.response.completion_tokens";
-        public const string Prompt = "gen_ai.content.prompt";
-        public const string Completion = "gen_ai.content.completion";
+        public const string InputTokens = "gen_ai.usage.input_tokens";
+        public const string OutputTokens = "gen_ai.usage.output_tokens";
         public const string Address = "server.address";
         public const string Port = "server.port";
         public const string AgentId = "gen_ai.agent.id";