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). This could result in styles having to be tweaked and subsequent tickets being created

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.