Spike: Define approach for edge hover labels/tooltips

[lornakelly]

Description

Investigate how edge hover labels or tooltips should be implemented in the diagram, including how to display edge metadata such as condition expressions. As part of this spike, evaluate whether this should be built using React Flow’s default edges or custom edge components that consume waypoint data from the layout layer. Based on the findings, create follow-up ticket(s) for implementation.

Motivation

Clarify the technical approach before implementation so edge hover behaviour can be added in a way that fits the chosen edge rendering model.

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.