Move contextual copy toast cleanup to editor dispose

src/renderer/src/components/editor/setup-contextual-copy.ts

@@ -294,6 +294,13 @@ export function setupContextualCopy({
   editorDomNode.addEventListener('mouseup', updateCopyHint, true)
   editorDomNode.addEventListener('keyup', updateCopyHint, true)
   editorInstance.onDidDispose(() => {
+    // Why: the confirmation toast timeout belongs to the Monaco editor that
+    // scheduled it, so editor disposal is the earliest reliable cleanup point.
+    if (copyToastTimeoutRef.current !== null) {
+      window.clearTimeout(copyToastTimeoutRef.current)
+      copyToastTimeoutRef.current = null
+      setCopyToast(null)
+    }
     if (primarySelectionTimer !== null) {
       window.clearTimeout(primarySelectionTimer)
       primarySelectionTimer = null

src/renderer/src/components/editor/useContextualCopySetup.tsx

@@ -1,4 +1,4 @@
-import React, { useRef, useState, useEffect, useCallback } from 'react'
+import React, { useRef, useState, useCallback } from 'react'
 import type { editor } from 'monaco-editor'
 import { setupContextualCopy } from './setup-contextual-copy'
 
@@ -6,15 +6,6 @@ export function useContextualCopySetup() {
   const [copyToast, setCopyToast] = useState<{ left: number; top: number } | null>(null)
   const copyToastTimeoutRef = useRef<number | null>(null)
 
-  useEffect(() => {
-    const toastRef = copyToastTimeoutRef
-    return () => {
-      if (toastRef.current !== null) {
-        window.clearTimeout(toastRef.current)
-      }
-    }
-  }, [])
-
   const setupCopy = useCallback(
     (
       editorInstance: editor.IStandaloneCodeEditor,