Python: restructure: Python samples into progressive 01-05 layout (#3862)

* restructure: Python samples into progressive 01-05 layout

- 01-get-started/: 6 numbered steps (hello agent → hosting)
- 02-agents/: all agent concept samples (tools, middleware, providers, etc.)
- 03-workflows/: ALL existing workflow samples preserved as-is
- 04-hosting/: azure-functions, durabletask, a2a
- 05-end-to-end/: demos, evaluation, hosted agents
- Old files moved to _to_delete/ for review
- Added AGENTS.md with structure documentation
- autogen-migration/ and semantic-kernel-migration/ preserved at root

* fix: switch to AzureOpenAI Foundry, fix CI failures

- Switch all 01-get-started samples to AzureOpenAIResponsesClient with
  Azure AI Foundry project endpoint (AZURE_AI_PROJECT_ENDPOINT +
  AZURE_OPENAI_RESPONSES_DEPLOYMENT_NAME + AzureCliCredential)
- Add _to_delete/ and 05-end-to-end/ to pyrightconfig.samples.json excludes
- Fix test paths in packages/ that referenced old getting_started/ dirs:
  durabletask conftest + streaming test, azurefunctions conftest,
  devui conftest + capture_messages + openai_sdk_integration
- Fix workflow_as_agent_human_in_the_loop.py import (sibling import)
- Update hosting READMEs and tool comment paths
- Replace root README.md with new structure overview
- Update AGENTS.md to document Azure OpenAI Foundry as default provider

* cleanup: remove _to_delete folder, copy resource files to active dirs

All files in _to_delete/ were either:
- Exact duplicates of files in the new structure (240 files)
- Same file with only comment path updates (100 files)
- One import-fix diff (workflow_as_agent_human_in_the_loop.py)
- One superseded minimal_sample.py

Resource files (sample.pdf, countries.json, employees.pdf, weather.json)
copied to 02-agents/sample_assets/ and 02-agents/resources/ since active
samples reference them.

* fix: address PR review comments, centralize resources, remove root duplicates

- Fix type annotation in 04_memory.py (string union -> proper types)
- Fix old sample paths in observability files
- Fix grammar/spelling in observability samples
- Move sample_assets/ and resources/ to shared/ folder
- Remove 8 duplicate observability files from 02-agents root
- Update resource path references in multimodal_input and provider samples

* fix: update broken links from old getting_started paths to new structure

- Update relative paths in READMEs: getting_started/ → 01-get-started/,
  02-agents/, 03-workflows/, 04-hosting/, 05-end-to-end/
- Fix absolute GitHub URLs in package READMEs
- Fix broken link in ollama package README

* fix: convert absolute GitHub URLs to relative paths for link checker

Absolute URLs to python/samples/ on main branch 404 until PR merges.
Converted to relative paths that linkspector can verify locally.

* fix: update link for handoff sample moved to orchestrations/

* fix: update chatkit-integration README path from demos/ to 05-end-to-end/

* fix: update broken links in orchestrations README to match flat directory structure

python/samples/02-agents/devui/in_memory_mode.py

@@ -0,0 +1,124 @@
+# Copyright (c) Microsoft. All rights reserved.
+
+"""Example of using Agent Framework DevUI with in-memory entity registration.
+
+This demonstrates the simplest way to serve agents and workflows as OpenAI-compatible API endpoints.
+Includes both agents and a basic workflow to showcase different entity types.
+"""
+
+import logging
+import os
+from typing import Annotated
+
+from agent_framework import Agent, Executor, WorkflowBuilder, WorkflowContext, handler, tool
+from agent_framework.azure import AzureOpenAIChatClient
+from agent_framework.devui import serve
+from typing_extensions import Never
+
+
+# NOTE: approval_mode="never_require" is for sample brevity. Use "always_require" in production; see samples/02-agents/tools/function_tool_with_approval.py and samples/02-agents/tools/function_tool_with_approval_and_threads.py.
+@tool(approval_mode="never_require")
+# Tool functions for the agent
+@tool(approval_mode="never_require")
+def get_weather(
+    location: Annotated[str, "The location to get the weather for."],
+) -> str:
+    """Get the weather for a given location."""
+    conditions = ["sunny", "cloudy", "rainy", "stormy"]
+    temperature = 53
+    return f"The weather in {location} is {conditions[0]} with a high of {temperature}°C."
+
+
+@tool(approval_mode="never_require")
+def get_time(
+    timezone: Annotated[str, "The timezone to get time for."] = "UTC",
+) -> str:
+    """Get current time for a timezone."""
+    from datetime import datetime
+
+    # Simplified for example
+    return f"Current time in {timezone}: {datetime.now().strftime('%H:%M:%S')}"
+
+
+# Basic workflow executors
+class UpperCase(Executor):
+    """Convert text to uppercase."""
+
+    @handler
+    async def to_upper(self, text: str, ctx: WorkflowContext[str]) -> None:
+        """Convert input to uppercase and forward to next executor."""
+        result = text.upper()
+        await ctx.send_message(result)
+
+
+class AddExclamation(Executor):
+    """Add exclamation mark to text."""
+
+    @handler
+    async def add_exclamation(self, text: str, ctx: WorkflowContext[Never, str]) -> None:
+        """Add exclamation and yield as workflow output."""
+        result = f"{text}!"
+        await ctx.yield_output(result)
+
+
+def main():
+    """Main function demonstrating in-memory entity registration."""
+    # Setup logging
+    logging.basicConfig(level=logging.INFO, format="%(message)s")
+    logger = logging.getLogger(__name__)
+
+    # Create Azure OpenAI chat client
+    client = AzureOpenAIChatClient(
+        api_key=os.environ.get("AZURE_OPENAI_API_KEY"),
+        azure_endpoint=os.environ.get("AZURE_OPENAI_ENDPOINT"),
+        api_version=os.environ.get("AZURE_OPENAI_API_VERSION", "2024-10-21"),
+        model_id=os.environ.get("AZURE_OPENAI_CHAT_DEPLOYMENT_NAME", "gpt-4o"),
+    )
+
+    # Create agents
+    weather_agent = Agent(
+        name="weather-assistant",
+        description="Provides weather information and time",
+        instructions=(
+            "You are a helpful weather and time assistant. Use the available tools to "
+            "provide accurate weather information and current time for any location."
+        ),
+        client=client,
+        tools=[get_weather, get_time],
+    )
+
+    simple_agent = Agent(
+        name="general-assistant",
+        description="A simple conversational agent",
+        instructions="You are a helpful assistant.",
+        client=client,
+    )
+
+    # Create a basic workflow: Input -> UpperCase -> AddExclamation -> Output
+    upper_executor = UpperCase(id="upper_case")
+    exclaim_executor = AddExclamation(id="add_exclamation")
+
+    basic_workflow = (
+        WorkflowBuilder(
+            name="Text Transformer",
+            description="Simple 2-step workflow that converts text to uppercase and adds exclamation",
+            start_executor=upper_executor,
+        )
+        .add_edge(upper_executor, exclaim_executor)
+        .build()
+    )
+
+    # Collect entities for serving
+    entities = [weather_agent, simple_agent, basic_workflow]
+
+    logger.info("Starting DevUI on http://localhost:8090")
+    logger.info("Entities available:")
+    logger.info("  - Agents: weather-assistant, general-assistant")
+    logger.info("  - Workflow: basic text transformer (uppercase + exclamation)")
+
+    # Launch server with auto-generated entity IDs
+    serve(entities=entities, port=8090, auto_open=True)
+
+
+if __name__ == "__main__":
+    main()