Add diagnostics for AKS

[jeremydvoss]

Description

Diagnostics will now be enabled specifically for App Service attach and AKS attach. Also removes diagnostics for App Service manual instrumentation. However, those would not be triggered anyways.

All SDK Contribution checklist:

• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.

General Guidelines and Best Practices

• Title of the pull request is clear and informative.
• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• Pull request includes test coverage for the included changes.

[azure-sdk]

API change check

API changes are not detected in this pull request.

[Copilot]

Pull Request Overview

This pull request updates diagnostic functionality to support both App Service and AKS attach scenarios while removing legacy diagnostics for manual instrumentation. Key changes include:

• Replacing the constant _IS_DIAGNOSTICS_ENABLED with the new function _is_diagnostics_enabled() in multiple modules.
• Updating unit tests across utilities and diagnostics modules to patch the new diagnostics function and support the AKS attach scenario.
• Updating the CHANGELOG to reflect the new diagnostics enabled for AKS attach.

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
sdk/monitor/azure-monitor-opentelemetry/tests/utils/test_utils.py	Updated tests to validate diagnostics enablement using patch decorators for App Service, AKS, and Functions attach scenarios.
sdk/monitor/azure-monitor-opentelemetry/tests/diagnostics/test_status_logger.py	Adjusted patch target from the old constant to the new _is_diagnostics_enabled() function.
sdk/monitor/azure-monitor-opentelemetry/tests/diagnostics/test_diagnostic_logging.py	Same as above—updated patch to target _is_diagnostics_enabled().
sdk/monitor/azure-monitor-opentelemetry/azure/monitor/opentelemetry/_utils/init.py	Imported and defined the new _is_diagnostics_enabled() function to reflect diagnostic enablement logic.
sdk/monitor/azure-monitor-opentelemetry/azure/monitor/opentelemetry/_diagnostics/status_logger.py	Updated conditional check to call _is_diagnostics_enabled() instead of using the constant.
sdk/monitor/azure-monitor-opentelemetry/azure/monitor/opentelemetry/_diagnostics/diagnostic_logging.py	Updated patch target from the constant to the _is_diagnostics_enabled() function.
sdk/monitor/azure-monitor-opentelemetry/CHANGELOG.md	Documented new diagnostics behavior for AKS attach.

Comments suppressed due to low confidence (1)

sdk/monitor/azure-monitor-opentelemetry/tests/utils/test_utils.py:65

• [nitpick] The order of patch decorator parameters may not match the typical decorator application order (which is bottom-to-top), potentially leading to confusion about which mock corresponds to which patched target. Consider reordering the mock parameters or adding inline comments to clarify the mapping.

def test_diagnostics_app_service_attach(self, attach_mock, app_service_mock, aks_mock, functions_mock):