Python: fix for logging setup

[eavanvalkenburg]

Motivation and Context

Closes: #2242

Description

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/core/agent_framework
_logging.py	9	1	88%	12
TOTAL	15462	2353	84%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
2218	127 💤	0 ❌	0 🔥	52.251s ⏱️

[Copilot]

Pull Request Overview

This PR fixes logging setup by moving the logging.basicConfig() call from module-level execution to a dedicated setup_logging() function, giving users explicit control over when logging is configured.

Key Changes:

• Introduced setup_logging() function in agent_framework._logging to encapsulate logging configuration
• Updated the observability sample to demonstrate the new logging setup pattern
• Added documentation explaining the opinionated logging format and how to use setup_logging()

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
python/packages/core/agent_framework/_logging.py	Moved logging.basicConfig() from module level into a new setup_logging() function and exported it via __all__
python/samples/getting_started/observability/setup_observability_with_parameters.py	Added import and call to setup_logging() to demonstrate the new logging configuration pattern
python/samples/getting_started/observability/README.md	Added documentation sections explaining the setup_logging() function and updated sample description to reference logging setup

[dmytrostruk]

nit:

Suggested change

	We also have an opinionated logging format, which you can setup using:
	Agent Framework also has an opinionated logging format, which you can setup using:

[dmytrostruk]

nit:

Suggested change

	We have a built-in logging configuration that works well with telemetry. It sets the format to a standard format that includes timestamp, pathname, line number, and log level. You can use that by calling the `setup_logging()` function from the `agent_framework` module.
	Agent Framework has a built-in logging configuration that works well with telemetry. It sets the format to a standard format that includes timestamp, pathname, line number, and log level. You can use that by calling the `setup_logging()` function from the `agent_framework` module.