Route awscrt logs through the logging module

[azkrishpy]

Issue #, if available:

Description of changes:

Route awscrt logs through Python's logging module so they're emitted alongside botocore, awscli, s3transfer, and urllib3 when --debug is set. This makes CRT-backed
features (e.g. CRT-based S3 transfers) easier to diagnose without configuring CRT logging separately.

• awscli/logger.py: switch from awscrt.io.init_logging to awscrt.logging.init_logging; enable/disable_crt_logging now use Python log levels.
• awscli/clidriver.py: add awscrt to the --debug logger list.
• Existing logger tests updated to mock the new awscrt.logging.set_log_level target.

Generated with AI assistance and reviewed by @azkrishpy

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