Respect log4j1.compatibility for programmatic configuration

[jhl221123]

This PR addresses issue #3667 by adding guard logic to methods in Category and LogManager that can modify the configuration. These changes ensure that programmatic configuration using the Log4j 1.x API is ignored unless the log4j1.compatibility flag is explicitly set to true.

I have confirmed the fix by running the reproducer provided in the issue, which now yields the following corrected output for the latest snapshot:

Testing 2.22.0
00:11:30.417 [main] INFO  org.example.App - Initializing Log4j 1.2 API...
00:11:30.423 [main] INFO  org.example.App - Log4j 1.2 API initialized.
Recorded 2 events (expected 2)

Testing 2.23.0
00:11:32.276 [main] INFO  org.example.App - Initializing Log4j 1.2 API...
Recorded 1 events (expected 2)

Testing 2.25.0
2025-07-09T15:11:36.970645Z main INFO Initializing Log4j 1.2 API...Recorded 1 events (expected 2)

Testing 2.26.0-SNAPSHOT
2025-07-09T15:11:39.258845Z main INFO Initializing Log4j 1.2 API...2025-07-09T15:11:39.262583Z main INFO Log4j 1.2 API initialized.Recorded 2 events (expected 2)

Additionally, I have updated the existing unit tests and added new tests to verify that the guard logic works as expected when the compatibility mode is disabled. I am not entirely confident that the new unit tests are perfect. Please let me know if there are any areas for improvement.

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[github-actions]

Job	Requested goals	Build Tool Version	Build Outcome	Build Scan®
build-macos-latest	clean install	3.9.8	❌
build-ubuntu-latest	clean install	3.9.8	✅
build-windows-latest	clean install	3.9.8	✅

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