Python: add(azure-ai): support reasoning config for AzureAIClient

[moonbox3]

Motivation and Context

With the current use of the AzureAIProjectAgentProvider, there's no handling for the reasoning config which some OpenAI reasoning models support.

Description

Add support for a reasoning config.

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines
• All unit tests pass, and I have added new tests where possible
• Is this a breaking change? If yes, add "[BREAKING]" prefix to the title of the PR.

[markwallace-microsoft]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
packages/azure-ai/agent_framework_azure_ai
_client.py	193	45	76%	248–251, 256, 259–262, 267, 270–271, 274, 281, 345, 347, 395, 423–426, 469, 506, 508, 513, 515–516, 519–522, 524, 526–527, 529–537, 539, 584
_project_provider.py	113	9	92%	126–127, 205, 303, 347, 380, 429–431
packages/core/agent_framework
_types.py	947	132	86%	71, 94–95, 149, 154, 173, 175, 179, 183, 185, 187, 189, 206–207, 209–211, 213–214, 216–217, 219–220, 235–237, 239–242, 259, 264, 269, 273, 299, 303, 647–648, 1019, 1081, 1098, 1116, 1121, 1139, 1147–1149, 1166–1167, 1169, 1187–1188, 1190, 1197–1198, 1200, 1235, 1246–1247, 1249, 1268–1269, 1272–1281, 1284–1287, 1289, 1293, 1327, 1360, 1532, 1537, 1541, 1545, 1737, 1747, 1792, 1837–1842, 1864, 1869, 2228, 2237, 2373, 2461–2463, 2502, 2558, 2579, 2588, 2817–2819, 2822–2824, 2828, 2833, 2837, 2949–2951, 2979, 3015, 3033, 3037–3039, 3041, 3052–3053, 3056–3060, 3066
TOTAL	17491	2706	84%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
3230	213 💤	0 ❌	0 🔥	1m 10s ⏱️

[Copilot]

Pull request overview

Adds support for configuring “reasoning” when working with Azure AI Project agents, along with a new sample and a unit test.

Changes:

• Pass reasoning from default_options into PromptAgentDefinition during agent creation in AzureAIProjectAgentProvider.
• Extend Azure AI client options typing to include reasoning and strip it from request-level options.
• Add a new getting-started sample demonstrating reasoning output, plus a provider unit test.

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
python/samples/getting_started/agents/azure_ai/azure_ai_with_reasoning.py	New sample showing how to configure reasoning and display reasoning vs answer content.
python/samples/getting_started/agents/azure_ai/README.md	Adds the new sample to the examples table.
python/packages/azure-ai/tests/test_provider.py	Adds a unit test ensuring reasoning is passed into the created agent definition.
python/packages/azure-ai/agent_framework_azure_ai/_project_provider.py	Wires default_options["reasoning"] into agent creation (PromptAgentDefinition).
python/packages/azure-ai/agent_framework_azure_ai/_client.py	Adds reasoning to options typing and excludes it from request-level run_options.