feat: add Copy, Paste, Select All commands to Edit menu (#8954)

## Summary

- Add Copy, Paste, and Select All commands to the Edit menu for
mobile/touch users and accessibility
- Menu-based copy uses LiteGraph internal clipboard; existing Ctrl+C/V
behavior is unchanged

## Changes

- `useCoreCommands.ts`: Register three new commands (`CopySelected`,
`PasteFromClipboard`, `SelectAll`)
- `coreMenuCommands.ts`: Add menu entries under Edit (between Undo/Redo
and Clear Workflow)
- `useCoreCommands.test.ts`: Add unit tests for the new commands

### AS IS
<img width="260" height="176" alt="스크린샷 2026-02-18 오후 5 44 14"
src="https://github.com/user-attachments/assets/8c9c86e1-55cc-411b-9d42-429001e04630"
/>


### TO BE
<img width="516" height="497" alt="스크린샷 2026-02-19 오후 5 07 28"
src="https://github.com/user-attachments/assets/a2047541-582f-4520-a08f-98c6e532d29f"
/>


## Test plan

- [x] Verify Copy/Paste/Select All appear in Edit menu
- [x] Select nodes → Edit > Copy → Edit > Paste → nodes duplicated
- [x] Edit > Select All → all canvas items selected
- [x] Copy with no selection → no-op (no error)
- [x] Existing Ctrl+C/V keyboard shortcuts still work

Fixes #2892

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8954-feat-add-Copy-Paste-Select-All-commands-to-Edit-menu-30b6d73d365081ec9270ed2a562eaf0b)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

src/composables/useCoreCommands.test.ts

@@ -23,7 +23,13 @@ vi.mock('vue-i18n', async () => {
 
 vi.mock('@/scripts/app', () => {
   const mockGraphClear = vi.fn()
-  const mockCanvas = { subgraph: undefined }
+  const mockCanvas = {
+    subgraph: undefined,
+    selectedItems: new Set(),
+    copyToClipboard: vi.fn(),
+    pasteFromClipboard: vi.fn(),
+    selectItems: vi.fn()
+  }
 
   return {
     app: {
@@ -105,7 +111,8 @@ vi.mock('@/stores/subgraphStore', () => ({
 
 vi.mock('@/renderer/core/canvas/canvasStore', () => ({
   useCanvasStore: vi.fn(() => ({
-    getCanvas: () => app.canvas
+    getCanvas: () => app.canvas,
+    canvas: app.canvas
   })),
   useTitleEditorStore: vi.fn(() => ({
     titleEditorTarget: null
@@ -300,6 +307,48 @@ describe('useCoreCommands', () => {
     })
   })
 
+  describe('Canvas clipboard commands', () => {
+    function findCommand(id: string) {
+      return useCoreCommands().find((cmd) => cmd.id === id)!
+    }
+
+    beforeEach(() => {
+      app.canvas.selectedItems = new Set()
+      vi.mocked(app.canvas.copyToClipboard).mockClear()
+      vi.mocked(app.canvas.pasteFromClipboard).mockClear()
+      vi.mocked(app.canvas.selectItems).mockClear()
+    })
+
+    it('should copy selected items when selection exists', async () => {
+      app.canvas.selectedItems = new Set([
+        {}
+      ]) as typeof app.canvas.selectedItems
+
+      await findCommand('Comfy.Canvas.CopySelected').function()
+
+      expect(app.canvas.copyToClipboard).toHaveBeenCalledWith()
+    })
+
+    it('should not copy when no items are selected', async () => {
+      await findCommand('Comfy.Canvas.CopySelected').function()
+
+      expect(app.canvas.copyToClipboard).not.toHaveBeenCalled()
+    })
+
+    it('should paste from clipboard', async () => {
+      await findCommand('Comfy.Canvas.PasteFromClipboard').function()
+
+      expect(app.canvas.pasteFromClipboard).toHaveBeenCalledWith()
+    })
+
+    it('should select all items', async () => {
+      await findCommand('Comfy.Canvas.SelectAll').function()
+
+      // No arguments means "select all items on canvas"
+      expect(app.canvas.selectItems).toHaveBeenCalledWith()
+    })
+  })
+
   describe('Subgraph metadata commands', () => {
     beforeEach(() => {
       mockSubgraph.extra = {}

src/composables/useCoreCommands.ts

@@ -884,6 +884,32 @@ export function useCoreCommands(): ComfyCommand[] {
         window.open(staticUrls.forum, '_blank')
       }
     },
+    {
+      id: 'Comfy.Canvas.CopySelected',
+      icon: 'icon-[lucide--copy]',
+      label: 'Copy',
+      function: () => {
+        if (app.canvas.selectedItems?.size) {
+          app.canvas.copyToClipboard()
+        }
+      }
+    },
+    {
+      id: 'Comfy.Canvas.PasteFromClipboard',
+      icon: 'icon-[lucide--clipboard-paste]',
+      label: 'Paste',
+      function: () => {
+        app.canvas.pasteFromClipboard()
+      }
+    },
+    {
+      id: 'Comfy.Canvas.SelectAll',
+      icon: 'icon-[lucide--lasso-select]',
+      label: 'Select All',
+      function: () => {
+        app.canvas.selectItems()
+      }
+    },
     {
       id: 'Comfy.Canvas.DeleteSelectedItems',
       icon: 'pi pi-trash',

src/constants/coreMenuCommands.ts

@@ -14,6 +14,14 @@ export const CORE_MENU_COMMANDS = [
     ]
   ],
   [['Edit'], ['Comfy.Undo', 'Comfy.Redo']],
+  [
+    ['Edit'],
+    [
+      'Comfy.Canvas.CopySelected',
+      'Comfy.Canvas.PasteFromClipboard',
+      'Comfy.Canvas.SelectAll'
+    ]
+  ],
   [['Edit'], ['Comfy.ClearWorkflow']],
   [['Edit'], ['Comfy.OpenClipspace']],
   [