Support for actionId and handle components in REDIRECT steps

[ThaminduR]

Issue

wso2/product-is#25415

This pull request introduces support for an explicit actionId property in the Component model, ensuring that button components have a clear action identifier. It also improves the conversion logic to consistently set actionId for buttons, updates API documentation examples, and refines handling of component lists in data conversion.

Model and API improvements:

• Added a new actionId property to the Component class and ensured it is included in equality, hash, and string methods. [1] [2] [3] [4] [5]
• Updated OpenAPI YAML (flow-execution.yaml) and Java annotations to use consistent examples for id and actionId, clarifying documentation. [1] [2] [3] [4]

Conversion logic enhancements:

• In Utils.java, modified the convertToComponent method to set actionId to the component's id for button components, ensuring correct action mapping.
• Improved the handling of the components list in convertToData to avoid nulls and ensure empty lists are returned when appropriate.

Code maintenance:

• Added missing import for ArrayList in Utils.java to support new logic.