fix: frontend memory leaks — Monaco dispose, TQ cache eviction, useEffect cleanup

- Dispose Monaco editor instances on dialog close to prevent cycle leak
- Replace gcTime: Infinity with finite TTLs and evict orphaned subscription queryKeys
- Add missing useEffect cleanup for timers, move setTimeout out of useMemo

src/components/setting/mods/dns-viewer.tsx

@@ -16,6 +16,7 @@ import {
 import { invoke } from '@tauri-apps/api/core'
 import { useLockFn } from 'ahooks'
 import yaml from 'js-yaml'
+import type { editor } from 'monaco-editor'
 import type { Ref } from 'react'
 import {
   useCallback,
@@ -189,6 +190,7 @@ export function DnsViewer({ ref }: { ref?: Ref<DialogRef> }) {
   const [open, setOpen] = useState(false)
   const [visualization, setVisualization] = useState(true)
   const skipYamlSyncRef = useRef(false)
+  const editorRef = useRef<editor.IStandaloneCodeEditor | null>(null)
   const [values, setValues] = useState<{
     enable: boolean
     listen: string
@@ -453,6 +455,13 @@ export function DnsViewer({ ref }: { ref?: Ref<DialogRef> }) {
     }
   }, [visualization])
 
+  useEffect(() => {
+    return () => {
+      editorRef.current?.dispose()
+      editorRef.current = null
+    }
+  }, [])
+
   const initDnsConfig = useCallback(async () => {
     try {
       const dnsConfigExists = await invoke<boolean>(
@@ -1057,6 +1066,9 @@ export function DnsViewer({ ref }: { ref?: Ref<DialogRef> }) {
           value={yamlContent}
           theme={themeMode === 'light' ? 'light' : 'vs-dark'}
           className="flex-grow"
+          onMount={(editorInstance) => {
+            editorRef.current = editorInstance
+          }}
           options={{
             tabSize: 2,
             minimap: {