feat: Add specification example workflows as Storybook stories

[lornakelly]

Description

Add Storybook stories for workflow examples from the specification’s examples/ directory. These stories should render the workflows in the editor to showcase supported structures and behaviours.

Initially, either include all examples or a representative subset (TBD)

Motivation

Provide workflow examples within Storybook to support development, testing, and demonstration of editor capabilities

Proposed Implementation

No response

Definition of Done

• Implementation: Fully implemented according to the Serverless Workflow spec.
• Unit Tests: Comprehensive unit tests are included and passing.
• Integration Tests: Verified within the monorepo and target environments (Web/VS Code).
• Documentation: Updated README.md, ADRs, or official docs.
• Performance: No significant regression in editor responsiveness.
• Accessibility: UI changes comply with accessibility standards.