Python: Properly handle AzureAI Search results for AzureAIAgent (#12654)

### Motivation and Context

After the Azure AI Agent service went to GA, there were some updates in
the underlying SDK. When there are azure_ai_search results while running
the agent, they no longer show up as attributes related to the tool
call. They are present in the dictionary, so our current code is failing
when trying to access the attribute. This PR updates how we form the
FunctionCallContent or FunctionResultContent for both azure_ai_search
streaming and non-streaming.

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### Description

Update how we form the FunctionCallContent or FunctionResultContent for
both azure_ai_search streaming and non-streaming for the AzureAIAgent.
- Closes #12422

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These notes will help understanding how your code works. Thanks! -->

### 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: moonbox3

python/semantic_kernel/agents/azure_ai/agent_content_generation.py

@@ -299,26 +299,33 @@ def generate_bing_grounding_content(
 @experimental
 def generate_azure_ai_search_content(
     agent_name: str, azure_ai_search_tool_call: "RunStepAzureAISearchToolCall"
-) -> ChatMessageContent:
+) -> ChatMessageContent | None:
     """Generate function result content related to an Azure AI Search Tool."""
-    message_content: ChatMessageContent = ChatMessageContent(role=AuthorRole.ASSISTANT, name=agent_name)  # type: ignore
+    items: list[FunctionCallContent | FunctionResultContent] = []
+
     # Azure AI Search tool call contains both tool call input and output
-    message_content.items.append(
-        FunctionCallContent(
-            id=azure_ai_search_tool_call.id,
-            name=azure_ai_search_tool_call.type,
-            function_name=azure_ai_search_tool_call.type,
-            arguments=azure_ai_search_tool_call.azure_ai_search.get("input"),
+    arguments = azure_ai_search_tool_call.azure_ai_search.get("input")
+    if arguments:
+        items.append(
+            FunctionCallContent(
+                id=azure_ai_search_tool_call.id,
+                name=azure_ai_search_tool_call.type,
+                function_name=azure_ai_search_tool_call.type,
+                arguments=arguments,
+                inner_content=azure_ai_search_tool_call,
+            )
         )
-    )
-    message_content.items.append(
-        FunctionResultContent(
-            function_name=azure_ai_search_tool_call.type,
-            id=azure_ai_search_tool_call.id,
-            result=azure_ai_search_tool_call.azure_ai_search.get("output"),
+    result = azure_ai_search_tool_call.azure_ai_search.get("output")
+    if result:
+        items.append(
+            FunctionResultContent(
+                function_name=azure_ai_search_tool_call.type,
+                id=azure_ai_search_tool_call.id,
+                result=result,
+                inner_content=azure_ai_search_tool_call,
+            )
         )
-    )
-    return message_content
+    return ChatMessageContent(role=AuthorRole.ASSISTANT, name=agent_name, items=items) if items else None  # type: ignore
 
 
 @experimental
@@ -506,29 +513,39 @@ def generate_streaming_azure_ai_search_content(
     for index, tool in enumerate(step_details.tool_calls):
         if tool.type == "azure_ai_search":
             azure_ai_search_tool = cast(RunStepAzureAISearchToolCall, tool)
-            arguments = getattr(azure_ai_search_tool, "azure_ai_search", None)
-            items.append(
-                FunctionCallContent(
-                    id=azure_ai_search_tool.id,
-                    index=index,
-                    name=azure_ai_search_tool.type,
-                    function_name=azure_ai_search_tool.type,
-                    arguments=arguments,
+            azure_ai_search_dict: dict = azure_ai_search_tool.get("azure_ai_search", None)
+            arguments = azure_ai_search_dict.get("input", {}) if azure_ai_search_dict else None
+            if arguments:
+                items.append(
+                    FunctionCallContent(
+                        id=azure_ai_search_tool.id,
+                        index=index,
+                        name=azure_ai_search_tool.type,
+                        function_name=azure_ai_search_tool.type,
+                        arguments=arguments,
+                        inner_content=azure_ai_search_tool,
+                    )
                 )
-            )
-            items.append(
-                FunctionResultContent(
-                    function_name=azure_ai_search_tool.type,
-                    id=azure_ai_search_tool.id,
-                    result=azure_ai_search_tool.azure_ai_search.get("output"),
+            result = azure_ai_search_dict.get("output", {}) if azure_ai_search_dict else None
+            if result:
+                items.append(
+                    FunctionResultContent(
+                        function_name=azure_ai_search_tool.type,
+                        id=azure_ai_search_tool.id,
+                        result=result,
+                        inner_content=azure_ai_search_tool,
+                    )
                 )
-            )
 
-    return StreamingChatMessageContent(
-        role=AuthorRole.ASSISTANT,
-        name=agent_name,
-        choice_index=0,
-        items=items,  # type: ignore
+    return (
+        StreamingChatMessageContent(
+            role=AuthorRole.ASSISTANT,
+            name=agent_name,
+            choice_index=0,
+            items=items,  # type: ignore
+        )
+        if items
+        else None
     )  # type: ignore