- New lib/crewai-core/ package: version, paths, constants, lock_store, user_data,
printer, telemetry. Pure leaf — depends only on appdirs/portalocker/rich/otel.
- crewai now depends on crewai-core; old crewai.utilities.{version,paths,printer,
lock_store} and the user-data block of events/listeners/tracing/utils.py become
one-shot DeprecationWarning shims that re-export from crewai_core.
- crewai-cli drops its hard dep on crewai and depends only on crewai-core. CLI
imports for telemetry/version/printer/constants now point at crewai_core.
- tools/main.py lazy-imports project_utils + get_user_id; the publish/login
subcommands print a friendly "requires crewai" error if it's missing.
- crewai-cli is now genuinely standalone: 'crewai --help', 'version', 'login',
'config', 'traces', 'create', 'template' all work without crewai installed.
- 351 CLI tests + 9 crewai-core smoke tests + crewai's full mypy (471 files) clean.
* Fix lock_store crash when redis package is not installed
`REDIS_URL` being set was enough to trigger a Redis lock, which would
raise `ImportError` if the `redis` package wasn't available. Added
`_redis_available()` to guard on both the env var and the import.
* Simplify tests
* Simplify tests #2
