[feat] Implement media asset workflow actions with shared utilities (#6696)

## Summary

Implements 4 missing media asset workflow features and creates shared
utilities to eliminate code duplication.

## Implemented Features

### 1. Copy Job ID ✅
- Properly extracts promptId using `getOutputAssetMetadata`
- Uses `useCopyToClipboard` composable

### 2. Add to Current Workflow ✅
- Adds LoadImage/LoadVideo/LoadAudio nodes to canvas
- Supports all media file types (JPEG, PNG, MP4, etc.)
- Auto-detects appropriate node type using `detectNodeTypeFromFilename`
utility

### 3. Open Workflow in New Tab ✅
- Extracts workflow from asset metadata or embedded PNG
- Opens workflow in new tab

### 4. Export Workflow ✅
- Exports workflow as JSON file
- Supports optional filename prompt

## Code Refactoring

### Created Shared Utilities:
1. **`assetTypeUtil.ts`** - `getAssetType()` function eliminates 6
instances of `asset.tags?.[0] || 'output'`
2. **`assetUrlUtil.ts`** - `getAssetUrl()` function consolidates 3 URL
construction patterns
3. **`workflowActionsService.ts`** - Shared service for workflow
export/open operations
4. **`workflowExtractionUtil.ts`** - Extract workflows from jobs/assets
5. **`loaderNodeUtil.ts`** - Detect loader node types from filenames

### Improvements to Existing Code:
- Refactored to use `formatUtil.getMediaTypeFromFilename()`
- Extracted `deleteAssetApi()` helper to reduce deletion logic
duplication (~40 lines)
- Moved `isResultItemType` type guard to shared `typeGuardUtil.ts`
- Added 9 i18n strings for proper localization
- Added `@comfyorg/shared-frontend-utils` dependency

## Input Assets Support

Improved input assets to support workflow features where applicable:
- ✅ All media files (JPEG/PNG/MP4, etc.) → "Add to current workflow"
enabled
- ✅ PNG/WEBP/FLAC with embedded metadata → "Open/Export workflow"
enabled

## Impact

- **~150+ lines** of duplicate code eliminated
- **5 new utility files** created to improve code reusability
- **11 files** changed, **483 insertions**, **234 deletions**

## Testing

✅ TypeScript typecheck passed  
✅ ESLint passed  
✅ Knip passed

🤖 Generated with [Claude Code](https://claude.com/claude-code)

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6696-feat-Implement-media-asset-workflow-actions-with-shared-utilities-2ab6d73d365081fb8ae9d71ce6e38589)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: GitHub Action <action@github.com>

src/platform/assets/utils/assetTypeUtil.ts

@@ -0,0 +1,24 @@
+/**
+ * Utilities for working with asset types
+ */
+
+import type { AssetItem } from '../schemas/assetSchema'
+
+/**
+ * Extract asset type from an asset's tags array
+ * Falls back to a default type if tags are not present
+ *
+ * @param asset The asset to extract type from
+ * @param defaultType Default type to use if tags are empty (default: 'output')
+ * @returns The asset type ('input', 'output', 'temp', etc.)
+ *
+ * @example
+ * getAssetType(asset) // Returns 'output' or first tag
+ * getAssetType(asset, 'input') // Returns 'input' if no tags
+ */
+export function getAssetType(
+  asset: AssetItem,
+  defaultType: 'input' | 'output' = 'output'
+): string {
+  return asset.tags?.[0] || defaultType
+}

src/platform/assets/utils/assetUrlUtil.ts

@@ -0,0 +1,29 @@
+/**
+ * Utilities for constructing asset URLs
+ */
+
+import { api } from '@/scripts/api'
+import type { AssetItem } from '../schemas/assetSchema'
+import { getAssetType } from './assetTypeUtil'
+
+/**
+ * Get the download/view URL for an asset
+ * Constructs the proper URL with filename encoding and type parameter
+ *
+ * @param asset The asset to get URL for
+ * @param defaultType Default type if asset doesn't have tags (default: 'output')
+ * @returns Full URL for viewing/downloading the asset
+ *
+ * @example
+ * const url = getAssetUrl(asset)
+ * downloadFile(url, asset.name)
+ */
+export function getAssetUrl(
+  asset: AssetItem,
+  defaultType: 'input' | 'output' = 'output'
+): string {
+  const assetType = getAssetType(asset, defaultType)
+  return api.apiURL(
+    `/view?filename=${encodeURIComponent(asset.name)}&type=${assetType}`
+  )
+}