Python: Improve/Simplify the Assistant Agents (microsoft#10666)

### Motivation and Context

The current abstractions we have around the Semantic Kernel Assistant
Agents are considered to be "fully-wrapped." This is beneficial in that
SK provides a tight/complete abstraction over the agent; however, it
doesn't scale well when new features are added to the underlying APIs
(OpenAI) - it requires updates from SK to make each and every update. It
also adds a lot more complexity in terms of needing to handle everything
in SK, requires more code coverage, and chances for bugs to surface due
to these complexities.

> **NOTE:** this update is _breaking_. We're moving to simplify the
abstractions/APIs before we move Assistant Agents from **experimental**
to GA.

Similar to how the `AzureAIAgent` was created, we're moving to a
"less-wrapped" abstraction around the OpenAI Assistant v2 APIs. We do
have some "convenience methods" on the Agents, via class methods, to
configure things like the code interpreter tool and resource, file
search tool and resource, the clients required to interact with the
Assistants, as well as being able to easily configure structured
outputs, similar to how it is done with a ChatCompletion (either provide
the Pydantic model or the Python class).

To work with Assistant Agents now, it's as simple as:

```python
from semantic_kernel.agents.open_ai import AzureAssistantAgent
from semantic_kernel.functions import kernel_function

class MenuPlugin:
   # Plugin code here using the @kernel_function decorator

# Create the client using Azure OpenAI resources and configuration
client, model = AzureAssistantAgent.setup_resources()

# Create the assistant definition
definition = await client.beta.assistants.create(
    model=model,
    instructions="Answer questions about the menu.",
    name="Host",
)

agent = AzureAssistantAgent(
    client=client,
    definition=definition,
    plugins=[MenuPlugin()],  # The plugins can be passed in as a list to the constructor
)

# Note: plugins can also be configured on the Kernel and passed in as a parameter to the OpenAIAssistantAgent

# Define a thread and invoke the agent with the user input
thread = await agent.client.beta.threads.create()
```

**I will create a migration guide (issue) showing what needs to be
updated from the previous usage to this new pattern.**

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### Description

This PR provides the new abstractions for the
`AzureAssistantAgent`/`OpenAIAssistantAgent` classes.
- Updates underlying code
- Updates samples showing new patterns
- Updates unit tests
- Updates READMEs.
- Closes microsoft#10605 

Samples will be updated accordingly to show new patterns.

<!-- Describe your changes, the overall approach, the underlying design.
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
- [ ] I didn't break anyone 😄

Author: moonbox3

python/samples/concepts/README.md

@@ -4,20 +4,51 @@
 
 ### Agents - Creating and using [agents](../../semantic_kernel/agents/) in Semantic Kernel
 
-- [Assistant Agent Chart Maker](./agents/assistant_agent/assistant_agent_chart_maker.py)
-- [Assistant Agent File Manipulation](./agents/assistant_agent/assistant_agent_file_manipulation.py)
-- [Assistant Agent File Manipulation Streaming](./agents/assistant_agent/assistant_agent_file_manipulation_streaming.py)
-- [Assistant Agent Retrieval](./agents/assistant_agent/assistant_agent_retrieval.py)
-- [Assistant Agent Streaming](./agents/assistant_agent/assistant_agent_streaming.py)
+#### [OpenAI Assistant Agent](../../semantic_kernel/agents/open_ai/open_ai_assistant_agent.py)
+
+- [OpenAI Assistant Chart Maker Streaming](./agents/openai_assistant/openai_assistant_chart_maker_streaming.py)
+- [OpenAI Assistant Chart Maker](./agents/openai_assistant/openai_assistant_chart_maker.py)
+- [OpenAI Assistant File Manipulation Streaming](./agents/openai_assistant/openai_assistant_file_manipulation_streaming.py)
+- [OpenAI Assistant File Manipulation](./agents/openai_assistant/openai_assistant_file_manipulation.py)
+- [OpenAI Assistant File Manipulation Streaming](./agents/openai_assistant/openai_assistant_file_manipulation_streaming.py)
+- [OpenAI Assistant Retrieval](./agents/openai_assistant/openai_assistant_retrieval.py)
+- [OpenAI Assistant Streaming](./agents/openai_assistant/openai_assistant_streaming.py)
+- [OpenAI Assistant Structured Outputs](./agents/openai_assistant/openai_assistant_structured_outputs.py)
+- [OpenAI Assistant Templating Streaming](./agents/openai_assistant/openai_assistant_templating_streaming.py)
+- [OpenAI Assistant Vision Streaming](./agents/openai_assistant/openai_assistant_vision_streaming.py)
+
+#### [Azure AI Agent](../../semantic_kernel/agents/azure_ai/azure_ai_agent.py)
+
+- [Azure AI Agent with Azure AI Search](./agents/azure_ai_agent/azure_ai_agent_azure_ai_search.py)
+- [Azure AI Agent File Manipulation](./agents/azure_ai_agent/azure_ai_agent_file_manipulation.py)
+- [Azure AI Agent Streaming](./agents/azure_ai_agent/azure_ai_agent_streaming.py)
+
+#### [Bedrock Agent](../../semantic_kernel/agents/bedrock/bedrock_agent.py)
+- [Bedrock Agent Simple Chat Streaming](./agents/bedrock_agent/bedrock_agent_simple_chat_streaming.py)
+- [Bedrock Agent Simple Chat](./agents/bedrock_agent/bedrock_agent_simple_chat.py)
+- [Bedrock Agent Update Agent](./agents/bedrock_agent/bedrock_agent_update_agent.py)
+- [Bedrock Agent Use Existing](./agents/bedrock_agent/bedrock_agent_use_existing.py)
+- [Bedrock Agent With Code Interpreter Streaming](./agents/bedrock_agent/bedrock_agent_with_code_interpreter_streaming.py)
+- [Bedrock Agent With Code Interpreter](./agents/bedrock_agent/bedrock_agent_with_code_interpreter.py)
+- [Bedrock Agent With Kernel Function Streaming](./agents/bedrock_agent/bedrock_agent_with_kernel_function_streaming.py)
+- [Bedrock Agent With Kernel Function](./agents/bedrock_agent/bedrock_agent_with_kernel_function.py)
+- [Bedrock Agent Mixed Chat Agents Streaming](./agents/bedrock_agent/bedrock_mixed_chat_agents_streaming.py)
+- [Bedrock Agent Mixed Chat Agents](./agents/bedrock_agent/bedrock_mixed_chat_agents.py)
+
+#### [Chat Completion Agent](../../semantic_kernel/agents/chat_completion/chat_completion_agent.py)
+
 - [Chat Completion Function Termination](./agents/chat_completion_agent/chat_completion_function_termination.py)
 - [Chat Completion History Reducer](./agents/chat_completion_agent/chat_completion_history_reducer.py)
-- [Mixed Chat Agents](./agents/mixed_chat/mixed_chat_agents.py)
+- [Chat Completion Templating](./agents/chat_completion_agent/chat_completion_templating.py)
+
+#### [Mixed Agent Group Chat](../../semantic_kernel/agents/group_chat/agent_group_chat.py)
+
 - [Mixed Chat Agents Plugins](./agents/mixed_chat/mixed_chat_agents_plugins.py)
+- [Mixed Chat Agents](./agents/mixed_chat/mixed_chat_agents.py)
 - [Mixed Chat Files](./agents/mixed_chat/mixed_chat_files.py)
 - [Mixed Chat Images](./agents/mixed_chat/mixed_chat_images.py)
 - [Mixed Chat Reset](./agents/mixed_chat/mixed_chat_reset.py)
 - [Mixed Chat Streaming](./agents/mixed_chat/mixed_chat_streaming.py)
-- [Bedrock Agent](./agents/bedrock_agent/README.md)
 
 ### Audio - Using services that support audio-to-text and text-to-audio conversion
 

python/samples/concepts/agents/README.md

@@ -7,7 +7,10 @@ This project contains a step by step guide to get started with _Semantic Kernel
 - For the use of Chat Completion agents, the minimum allowed Semantic Kernel pypi version is 1.3.0.
 - For the use of OpenAI Assistant agents, the minimum allowed Semantic Kernel pypi version is 1.4.0.
 - For the use of Agent Group Chat, the minimum allowed Semantic kernel pypi version is 1.6.0.
-- For the use of Streaming OpenAI Assistant agents, the minimum allowed Semantic Kernel pypi version is 1.11.0
+- For the use of Streaming OpenAI Assistant agents, the minimum allowed Semantic Kernel pypi version is 1.11.0.
+- For the use of AzureAI and Bedrock agents, the minimum allowed Semantic Kernel pypi version is 1.21.0.
+- For the use of Crew.AI as a plugin, the minimum allowed Semantic Kernel pypi version is 1.21.1.
+
 
 ## Source
 
@@ -20,12 +23,12 @@ The concept agents examples are grouped by prefix:
 Prefix|Description
 ---|---
 assistant|How to use agents based on the [Open AI Assistant API](https://platform.openai.com/docs/assistants).
-chat_completion|How to use Semantic Kernel Chat Completion agents.
-bedrock|How to use AWS Bedrock agents in Semantic Kernel.
+autogen_conversable_agent| How to use [AutoGen 0.2 Conversable Agents](https://microsoft.github.io/autogen/0.2/docs/Getting-Started) within Semantic Kernel.
+azure_ai_agent|How to use an [Azure AI Agent](https://learn.microsoft.com/en-us/azure/ai-services/agents/quickstart?pivots=programming-language-python-azure) within Semantic Kernel.
+chat_completion_agent|How to use Semantic Kernel Chat Completion agents that leverage AI Connector Chat Completion APIs.
+bedrock|How to use [AWS Bedrock agents](https://aws.amazon.com/bedrock/agents/) in Semantic Kernel.
 mixed_chat|How to combine different agent types.
-complex_chat|**Coming Soon**
-
-_Note: As we strive for parity with .NET, more getting_started_with_agent samples will be added. The current steps and names may be revised to further align with our .NET counterpart._
+openai_assistant|How to use [OpenAI Assistants](https://platform.openai.com/docs/assistants/overview) in Semantic Kernel.
 
 ## Configuring the Kernel