Python: chore(python): improve dependency range automation

[eavanvalkenburg]

Summary

• tighten dependency bounds and coding standards guidance
• add dependency range validation workflow with issue/PR automation
• update related tests and dependency pins for compatibility

Closes #902

[Copilot]

Pull request overview

This PR improves Python dependency management automation by introducing a comprehensive dependency range validation system, tightening dependency bounds across packages, and enhancing test organization.

Changes:

• Adds automated dependency range validation script and GitHub Actions workflow to continuously validate and update dependency upper bounds
• Tightens dependency version constraints across all packages to follow documented standards for stable (>=1.0.0), prerelease, and pre-1.0 dependencies
• Improves test organization by adding @pytest.mark.integration markers and moving Azure-specific embedding tests to a dedicated file
• Updates coding standards documentation with clearer dependency versioning guidelines and corrects code examples

Reviewed changes

Copilot reviewed 33 out of 35 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
python/scripts/validate_dependency_ranges.py	New script that validates dependency ranges by testing candidate versions and updating pyproject.toml files
.github/workflows/python-dependency-range-validation.yml	New workflow that runs validation, creates issues for failures, and opens PRs with updated bounds
python/pyproject.toml	Adds validate-dependency-ranges poe task
python/packages/*/pyproject.toml	Tightens dependency bounds and adds integration test markers to test commands
python/packages/core/tests/openai/test_openai_embedding_client.py	Removes Azure tests (moved to dedicated file) and adds integration markers
python/packages/core/tests/azure/test_azure_embedding_client.py	New file with Azure OpenAI embedding tests and proper test isolation
python/packages/azure-ai-search/tests/test_aisearch_context_provider.py	Adds fixture to clear ambient Azure Search environment variables for test isolation
python/CODING_STANDARD.md	Clarifies external dependency versioning guidelines and fixes code example
python/packages/core/agent_framework/_types.py	Reorders docstring sections (Returns before Raises) following Python conventions
python/packages/core/agent_framework/_workflows/_workflow.py	Style improvement: combines variable assignment and yield statements
python/packages/devui/agent_framework_devui/_deployment.py	Style improvement: combines variable assignment and yield statements
python/packages/azurefunctions/agent_framework_azurefunctions/_app.py	Reorders docstring sections (Returns before Raises)
.gitignore	Adds dependency-range-results.json to ignored files

[markwallace-microsoft]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
packages/core/agent_framework
_agents.py	342	43	87%	435, 439, 491, 856, 892, 908, 991–994, 1055–1057, 1178, 1194, 1196, 1209, 1215, 1251, 1253, 1262–1267, 1272, 1274, 1280–1281, 1288, 1290–1291, 1299–1300, 1303–1305, 1313–1314, 1316, 1321, 1323
packages/core/agent_framework/_workflows
_workflow.py	267	19	92%	88, 269–271, 273–274, 292, 296, 430, 618, 639, 695, 707, 713, 718, 738–740, 753
TOTAL	22222	2758	87%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
4714	247 💤	0 ❌	0 🔥	1m 20s ⏱️

[TaoChenOSU]

These two scripts have very little comments. Perhaps a README to document how they work.

[dmytrostruk]

Please add short comment to describe the purpose of this workflow.