# A/B Deploy Diff Panel

## Module
Web

## Status
IMPLEMENTED

## Description
Full deployment diff panel comparing security state between two image versions (A/B) with SBOM side-by-side view, component diff rows, policy hit annotations, override dialog, and deploy action bar. Enables visual security review before promotion.

## Implementation Details
- **Feature directory**: `src/Web/StellaOps.Web/src/app/features/deploy-diff/`
- **Routes**: `deploy-diff.routes.ts`
- **Components**:
  - `component-diff-row` (`src/Web/StellaOps.Web/src/app/features/deploy-diff/components/component-diff-row/component-diff-row.component.ts`)
  - `deploy-action-bar` (`src/Web/StellaOps.Web/src/app/features/deploy-diff/components/deploy-action-bar/deploy-action-bar.component.ts`)
  - `deploy-diff-panel` (`src/Web/StellaOps.Web/src/app/features/deploy-diff/components/deploy-diff-panel/deploy-diff-panel.component.ts`)
  - `override-dialog` (`src/Web/StellaOps.Web/src/app/features/deploy-diff/components/override-dialog/override-dialog.component.ts`)
  - `policy-hit-annotation` (`src/Web/StellaOps.Web/src/app/features/deploy-diff/components/policy-hit-annotation/policy-hit-annotation.component.ts`)
  - `sbom-side-by-side` (`src/Web/StellaOps.Web/src/app/features/deploy-diff/components/sbom-side-by-side/sbom-side-by-side.component.ts`)
- **Services**:
  - `deploy-diff` (`src/Web/StellaOps.Web/src/app/features/deploy-diff/services/deploy-diff.service.ts`)
- **Models**:
  - `src/Web/StellaOps.Web/src/app/features/deploy-diff/models/deploy-diff.models.ts`
- **Source**: batch_38/file_18.md

## E2E Test Plan
- **Setup**:
  - [ ] Log in with a user that has appropriate permissions
  - [ ] Navigate to `/deploy-diff`
  - [ ] Ensure test data exists (scanned artifacts, SBOM data, or seed data as needed)
- **Core verification**:
  - [ ] Verify the panel/drawer opens on trigger (click, keyboard shortcut)
  - [ ] Verify the panel displays the correct detail data for the selected item
  - [ ] Verify the panel can be closed (X button, Escape key, backdrop click)
- **Edge cases**:
  - [ ] Verify graceful handling when backend API is unavailable (error state)
  - [ ] Verify responsive layout at different viewport sizes
  - [ ] Verify accessibility (keyboard navigation, screen reader labels, ARIA attributes)