fix: add Safari requestIdleCallback polyfill (#5664)

## Summary

Implemented cross-browser requestIdleCallback polyfill to fix Safari
crashes during graph initialization.

## Changes

- **What**: Added
[requestIdleCallback](https://developer.mozilla.org/en-US/docs/Web/API/Window/requestIdleCallback)
polyfill following [VS Code's
pattern](https://github.com/microsoft/vscode/blob/main/src/vs/base/common/async.ts)
with setTimeout fallback for Safari
- **Breaking**: None - maintains existing GraphView behavior

## Review Focus

Safari compatibility testing and timeout handling in the 15ms fallback
window. Verify that initialization tasks (keybindings, server config,
model loading) still execute properly on Safari iOS.

## References

- [VS Code async.ts
implementation](https://github.com/microsoft/vscode/blob/main/src/vs/base/common/async.ts)
- Source pattern for our polyfill
- [MDN
requestIdleCallback](https://developer.mozilla.org/en-US/docs/Web/API/Window/requestIdleCallback)
- Browser API documentation
- [Safari requestIdleCallback
support](https://caniuse.com/requestidlecallback) - Browser
compatibility table

Fixes CLOUD-FRONTEND-STAGING-N

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-5664-fix-add-Safari-requestIdleCallback-polyfill-2736d73d365081cdbcf1fb816fe098d6)
by [Unito](https://www.unito.io)

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

src/base/common/async.ts

@@ -0,0 +1,98 @@
+/**
+ * Cross-browser async utilities for scheduling tasks during browser idle time
+ * with proper fallbacks for browsers that don't support requestIdleCallback.
+ *
+ * Implementation based on:
+ * https://github.com/microsoft/vscode/blob/main/src/vs/base/common/async.ts
+ */
+
+interface IdleDeadline {
+  didTimeout: boolean
+  timeRemaining(): number
+}
+
+interface IDisposable {
+  dispose(): void
+}
+
+/**
+ * Internal implementation function that handles the actual scheduling logic.
+ * Uses feature detection to determine whether to use native requestIdleCallback
+ * or fall back to setTimeout-based implementation.
+ */
+let _runWhenIdle: (
+  targetWindow: any,
+  callback: (idle: IdleDeadline) => void,
+  timeout?: number
+) => IDisposable
+
+/**
+ * Execute the callback during the next browser idle period.
+ * Falls back to setTimeout-based scheduling in browsers without native support.
+ */
+export let runWhenGlobalIdle: (
+    callback: (idle: IdleDeadline) => void,
+    timeout?: number
+  ) => IDisposable
+
+  // Self-invoking function to set up the idle callback implementation
+;(function () {
+  const safeGlobal: any = globalThis
+
+  if (
+    typeof safeGlobal.requestIdleCallback !== 'function' ||
+    typeof safeGlobal.cancelIdleCallback !== 'function'
+  ) {
+    // Fallback implementation for browsers without native support (e.g., Safari)
+    _runWhenIdle = (_targetWindow, runner, _timeout?) => {
+      setTimeout(() => {
+        if (disposed) {
+          return
+        }
+
+        // Simulate IdleDeadline - give 15ms window (one frame at ~64fps)
+        const end = Date.now() + 15
+        const deadline: IdleDeadline = {
+          didTimeout: true,
+          timeRemaining() {
+            return Math.max(0, end - Date.now())
+          }
+        }
+
+        runner(Object.freeze(deadline))
+      })
+
+      let disposed = false
+      return {
+        dispose() {
+          if (disposed) {
+            return
+          }
+          disposed = true
+        }
+      }
+    }
+  } else {
+    // Native requestIdleCallback implementation
+    _runWhenIdle = (targetWindow: typeof safeGlobal, runner, timeout?) => {
+      const handle: number = targetWindow.requestIdleCallback(
+        runner,
+        typeof timeout === 'number' ? { timeout } : undefined
+      )
+
+      let disposed = false
+      return {
+        dispose() {
+          if (disposed) {
+            return
+          }
+          disposed = true
+          targetWindow.cancelIdleCallback(handle)
+        }
+      }
+    }
+  }
+
+  runWhenGlobalIdle = (runner, timeout) =>
+    _runWhenIdle(globalThis, runner, timeout)
+})()

src/views/GraphView.vue

@@ -33,6 +33,7 @@ import {
 } from 'vue'
 import { useI18n } from 'vue-i18n'
 
+import { runWhenGlobalIdle } from '@/base/common/async'
 import MenuHamburger from '@/components/MenuHamburger.vue'
 import UnloadWindowConfirmDialog from '@/components/dialog/UnloadWindowConfirmDialog.vue'
 import GraphCanvas from '@/components/graph/GraphCanvas.vue'
@@ -253,33 +254,30 @@ void nextTick(() => {
 })
 
 const onGraphReady = () => {
-  requestIdleCallback(
-    () => {
-      // Setting values now available after comfyApp.setup.
-      // Load keybindings.
-      wrapWithErrorHandling(useKeybindingService().registerUserKeybindings)()
+  runWhenGlobalIdle(() => {
+    // Setting values now available after comfyApp.setup.
+    // Load keybindings.
+    wrapWithErrorHandling(useKeybindingService().registerUserKeybindings)()
 
-      // Load server config
-      wrapWithErrorHandling(useServerConfigStore().loadServerConfig)(
-        SERVER_CONFIG_ITEMS,
-        settingStore.get('Comfy.Server.ServerConfigValues')
-      )
+    // Load server config
+    wrapWithErrorHandling(useServerConfigStore().loadServerConfig)(
+      SERVER_CONFIG_ITEMS,
+      settingStore.get('Comfy.Server.ServerConfigValues')
+    )
 
-      // Load model folders
-      void wrapWithErrorHandlingAsync(useModelStore().loadModelFolders)()
+    // Load model folders
+    void wrapWithErrorHandlingAsync(useModelStore().loadModelFolders)()
 
-      // Non-blocking load of node frequencies
-      void wrapWithErrorHandlingAsync(
-        useNodeFrequencyStore().loadNodeFrequencies
-      )()
+    // Non-blocking load of node frequencies
+    void wrapWithErrorHandlingAsync(
+      useNodeFrequencyStore().loadNodeFrequencies
+    )()
 
-      // Node defs now available after comfyApp.setup.
-      // Explicitly initialize nodeSearchService to avoid indexing delay when
-      // node search is triggered
-      useNodeDefStore().nodeSearchService.searchNode('')
-    },
-    { timeout: 1000 }
-  )
+    // Node defs now available after comfyApp.setup.
+    // Explicitly initialize nodeSearchService to avoid indexing delay when
+    // node search is triggered
+    useNodeDefStore().nodeSearchService.searchNode('')
+  }, 1000)
 }
 </script>