Enchance transaction checks to support conditional execution and non-blocking steps.

Currently, any single failure in the transaction flow causes the entire check to fail, even if the failure is from a non-critical or intermittent element. This reduces the reliability of our monitoring and increases false positives.

Proposed improvements:

1. Conditional steps:

   • Allow branching logic based on page state (e.g., if element A exists, proceed with flow A; otherwise follow fallback flow B).

   • This is especially useful for handling intermittent UI variations like popups, banners, or A/B testing elements.

2. Optional / non-blocking steps:

   • Allow certain steps to fail without terminating the entire transaction.

   • These steps can be marked as "warning" instead of "critical failure".

3. Continue-on-error capability:

   • Introduce a setting to continue execution even if a step fails, with proper logging.

   • This helps identify partial failures without losing visibility into later steps.