Python: Add more packages to unit test coverage gate

[TaoChenOSU]

Motivation and Context

Part of #2474

Description

Adding the following packages to the gate:

• packages.core.agent_framework: closes Python: Unit test coverage for core (other modules) #3360
• packages.core.agent_framework._workflows: closes Python: Unit test coverage for core/workflows module #3359
• packages.purview.agent_framework_purview: closes Python: purview package unit test coverage tracking #3358

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.

[Copilot]

Pull request overview

Updates the Python unit test coverage gate configuration to enforce the 85% threshold for additional GA packages, aligning with the repo’s coverage-tracking issues.

Changes:

• Add agent_framework_azure_ai_search to the consolidated poe all-tests-cov coverage sources.
• Enforce coverage threshold for packages.azure-ai-search.agent_framework_azure_ai_search, packages.core.agent_framework, and packages.core.agent_framework._workflows in the coverage gate script.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
python/pyproject.toml	Adds Azure AI Search package to the all-tests-cov pytest-cov source list so it appears in the Cobertura report.
.github/workflows/python-check-coverage.py	Expands the enforced module set so these packages now fail the build if below the configured coverage threshold.

[markwallace-microsoft]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
packages/core/agent_framework/_workflows
_agent.py	346	65	81%	59, 67–73, 107–108, 350–351, 357–358, 364, 366, 371, 454–455, 464, 471, 497, 530–532, 534, 536, 538, 543, 548, 595, 625, 642, 681–684, 690, 696, 700–701, 704–710, 714–715, 721, 782, 789, 795–796, 807, 839, 846, 867, 876, 880, 882–884, 891
TOTAL	21367	3428	83%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
4012	225 💤	0 ❌	0 🔥	1m 10s ⏱️