feat: integrate TypeScript SDK (spec 1.0) into diagram editor

[lornakelly]

Description

Add support for the TypeScript SDK (spec 1.0) and integrate it with the diagram editor component.

The editor should be able to accept workflows as:

• raw YAML
• raw JSON

Motivation

Introducing the TypeScript SDK will:

• ensure alignment with the Serverless Workflow spec (1.0)
• provide a consistent and typed model for workflows
• improve developer experience when working programmatically with workflows

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.