Move user-facing utilities from airflow.utils.* to Task SDK definitions

### Description Move user-facing utilities from airflow.utils.* directly into Task SDK definition modules where they logically belong, creating deprecation shims for backward compatibility. Files to move: - airflow.utils.state → airflow.sdk.definitions.state - airflow.utils.trigger_rule → airflow.sdk.definitions.trigger_rule - airflow.utils.weight_rule → airflow.sdk.definitions.weight_rule - airflow.utils.types → airflow.sdk.definitions.types - airflow.utils.operator_resources → airflow.sdk.definitions.resources - airflow.utils.task_group → merge into airflow.sdk.definitions.taskgroup - airflow.utils.context → merge into airflow.sdk.definitions.context - airflow.utils.decorators → merge into airflow.sdk.definitions.decorators - airflow.utils.module_loading → airflow.sdk.definitions._internal.module_loading - airflow.utils.helpers → airflow.sdk.definitions._internal.templating ### Use case/motivation _No response_ ### Related issues https://github.com/apache/airflow/issues/51671 ### Are you willing to submit a PR? - [x] Yes I am willing to submit a PR! ### Code of Conduct - [x] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)