Fit view to bounds (#1474)

* fit view:
- fit view to canvas selection
- fit view to whole graph when nothing is selected
- add button to graph canvas menu
- assign default keybinding '.'

* Adjust on changed APIs

* Update litegraph

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Co-authored-by: huchenlei <huchenlei@proton.me>

src/scripts/app.ts

@@ -27,6 +27,7 @@ import { ComfyAppMenu } from './ui/menu/index'
 import { getStorageValue } from './utils'
 import { ComfyWorkflow } from '@/stores/workflowStore'
 import {
+  LGraphGroup,
   LGraphCanvas,
   LGraph,
   LGraphNode,