Combine workflow and aworkflow (and Other Annotations)

[nirga]

OpenLLMetry currently separates annotations for synchronous and asynchronous functions (e.g., @workflow and @aworkflow). This approach introduces redundancy and complexity. We propose unifying these into single, flexible decorators (e.g., @workflow) that handle both sync and async functions seamlessly. This change should extend to all annotations with similar patterns.

Proposed Changes:
1. Create unified decorators for @workflow, @task, and similar annotations.
2. Enhance internal logic to automatically detect and handle function types.
3. Update annotations documentation with clear examples.
4. Deprecate old annotations with migration guidance.

Tasks:
• Design and implement unified decorators.
• Update tests and documentation for all affected annotations.
• Deprecate old annotations with clear migration steps.

Benefits:
Streamlines API usage across the board, reduces complexity, and makes OpenLLMetry more intuitive and maintainable.