Python: Bing custom search tool content support (#12415)

### Motivation and Context

In the `azure-ai-agent` package version 1.1.0b1, they provided the
`AgentsNamedToolChoiceType.BING_CUSTOM_SEARCH` enum. Adding this to then
provide support for generating bing grounding content for
streaming/non-streaming path.

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### Description

- Add BING_CUSTOM_SEARCH enum to allow for content support.
- Bumps `pyproject.toml` `azure-ai-agents` min allowed version to
`1.1.0b1` which includes this new enum.

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### Contribution Checklist

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- [X] The code builds clean without any errors or warnings
- [X] The PR follows the [SK Contribution
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Author: moonbox3

python/pyproject.toml

@@ -25,7 +25,7 @@ classifiers = [
 dependencies = [
     # azure agents
     "azure-ai-projects >= 1.0.0b11",
-    "azure-ai-agents >= 1.0.0",
+    "azure-ai-agents >= 1.1.0b1",
     "aiohttp ~= 3.8",
     "cloudevents ~=1.0",
     "pydantic >=2.0,!=2.10.0,!=2.10.1,!=2.10.2,!=2.10.3,<2.12",

python/semantic_kernel/agents/azure_ai/agent_thread_actions.py

@@ -285,7 +285,10 @@ def sort_key(step: RunStep):
                                         function_step=function_step,
                                         tool_call=tool_call,  # type: ignore
                                     )
-                                case AgentsNamedToolChoiceType.BING_GROUNDING:
+                                case (
+                                    AgentsNamedToolChoiceType.BING_GROUNDING
+                                    | AgentsNamedToolChoiceType.BING_CUSTOM_SEARCH
+                                ):
                                     logger.debug(
                                         f"Entering tool_calls (bing_grounding) for run [{run.id}], agent "
                                         f" `{agent.name}` and thread `{thread_id}`"
@@ -528,7 +531,10 @@ async def _process_stream_events(
                                 case AgentsNamedToolChoiceType.CODE_INTERPRETER:
                                     content = generate_streaming_code_interpreter_content(agent.name, details)
                                     content_is_visible = True
-                                case AgentsNamedToolChoiceType.BING_GROUNDING:
+                                case (
+                                    AgentsNamedToolChoiceType.BING_GROUNDING
+                                    | AgentsNamedToolChoiceType.BING_CUSTOM_SEARCH
+                                ):
                                     content = generate_streaming_bing_grounding_content(
                                         agent_name=agent.name, step_details=details
                                     )