fix(workflow): improve selected edge visibility

[BillLeoutsakosvl346]

Summary

Improves selected edge visibility with a full-opacity neutral highlight while preserving diff, execution, success, and error colors.

Synchronizes the transient edge-selection map with React Flow so mouse and keyboard selection, deselection, endpoint highlighting, z-order, and deletion stay aligned without persisting selection state.

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation
• Other: ___________

Testing

• bun run test -- workflow-edge-view-mount.test.tsx canvas-layers.test.ts in packages/workflow-renderer — 25 passed
• bun run test -- workflow-canvas-helpers.test.ts edge-highlight.test.ts use-shift-selection-lock.test.tsx in apps/sim — 21 passed
• bun run type-check in packages/workflow-renderer
• bun run type-check in apps/sim
• Biome check on all 11 changed files
• Browser-tested on localhost with a three-block, two-edge workflow: click selection, modifier selection state handling, pane and Escape deselection, Enter and Space selection with visible focus, matching endpoint highlights, delete button and keyboard deletion, Undo restoration, light and dark themes, and a clean console in a fresh workflow tab

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)

Screenshots/Videos

Proof screenshots are attached in the first PR comment.

[vercel]

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1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
docs	Skipped		Aug 28, 2026 12:46am

[greptile-apps]

Greptile Summary

The PR improves selected-edge visibility and synchronizes transient edge selection with React Flow without persisting selection state.

• Adds neutral full-opacity highlighting and focus styling for selected edges while preserving semantic status colors.
• Synchronizes mouse and keyboard selection, endpoint highlighting, z-order, and deletion controls.
• Adds selection-helper, interaction, and renderer tests.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains, and the previously reported import-convention issue is fixed at the current head.

Important Files Changed

Filename	Overview
apps/sim/app/workspace/[workspaceId]/w/[workflowId]/workflow.tsx	Synchronizes React Flow edge-selection changes with transient canvas state and gates deletion controls by edit permission.
apps/sim/app/workspace/[workspaceId]/w/[workflowId]/utils/workflow-canvas-helpers.ts	Adds stable context-aware selection keys and immutable application of edge-selection changes.
packages/workflow-renderer/src/edge/workflow-edge-view.tsx	Updates selected-edge appearance and renders an accessible delete control only when deletion is available.
apps/sim/app/workspace/[workspaceId]/w/[workflowId]/utils/edge-highlight.test.ts	Tests direct edge highlighting and now follows the established application path-alias convention.

_{Reviews (2): Last reviewed commit: "test(workflow): use edge highlight impor..." | Re-trigger Greptile}

[cubic-dev-ai]

No issues found across 11 files

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

_{Re-trigger cubic}

[BillLeoutsakosvl346]

@greptileai

[BillLeoutsakosvl346]