Refactor & code Cleanup in scenario

[Mips2648]

Description

This pull request focuses on improving exception handling and code consistency in the scenario and scenarioExpression classes, as well as making minor improvements to type safety and return logic. The main changes involve consolidating exception handling to use \Throwable, refactoring logging calls to use a static method, and ensuring type consistency for timeout values.

Exception Handling Improvements:

• Replaced multiple catch blocks for Exception and Error with a single catch (\Throwable $ex) in scenario.class.phpandscenarioExpression.class.php`

Logging Refactor & code Cleanup::**

• Updated all instance calls to $this->setLog to use static method self::setLog in scenarioExpression.class.php,
• Refactored logging in the wait static method to use the static setLog method, further standardizing logging practices.

Type and Return Consistency:

• Changed the getTimeout method in scenario.class.php to always return an int and removed the unused $_default parameter.
• Ensured the setTimeout method casts the timeout value to int before assignment for type safety.

Minor Logic Fixes:

• Added a missing return $return; statement in the export method to ensure the correct value is returned in all cases.

Suggested changelog entry

Various bugfix & quality improvement

Related issues/external references

Fixes #

Types of changes

• Code quality
• Bug fix (non-breaking change which fixes)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
  • This change is only breaking for integrators, not for external standards or end-users.
• Documentation improvement

PR checklist

• I have checked there is no other PR open for the same change.
• I have read the [La ligne directrice pour contribuer à ce projet / Contribution guidelines for this project).
• I grant the project the right to include and distribute the code under the GNU.
• I have added tests to cover my changes.
• I have verified that the code complies with the projects coding standards.
• [Required for new sniffs] I have added MD documentation for the sniff.