refactor(proxy): update proxy handling logic in useAppInit and GeneralSettings (#9081)

- Simplified proxy setting logic by removing unnecessary dispatches for 'system' and 'none' modes.
- Updated useAppInit to set proxy to undefined for 'system' mode and clarified direct mode handling with comments.

src/renderer/src/hooks/useAppInit.ts

@@ -86,11 +86,12 @@ export function useAppInit() {
 
   useEffect(() => {
     if (proxyMode === 'system') {
-      window.api.setProxy('system', proxyBypassRules)
+      window.api.setProxy('system', undefined)
     } else if (proxyMode === 'custom') {
       proxyUrl && window.api.setProxy(proxyUrl, proxyBypassRules)
     } else {
-      window.api.setProxy('')
+      // set proxy to none for direct mode
+      window.api.setProxy('', undefined)
     }
   }, [proxyUrl, proxyMode, proxyBypassRules])
 

src/renderer/src/pages/settings/GeneralSettings.tsx

@@ -113,12 +113,6 @@ const GeneralSettings: FC = () => {
 
   const onProxyModeChange = (mode: 'system' | 'custom' | 'none') => {
     dispatch(setProxyMode(mode))
-    if (mode === 'system') {
-      dispatch(_setProxyUrl(undefined))
-    } else if (mode === 'none') {
-      dispatch(_setProxyUrl(undefined))
-      dispatch(_setProxyBypassRules(undefined))
-    }
   }
 
   const languagesOptions: { value: LanguageVarious; label: string; flag: string }[] = [