Fix: Resolve account login issues in Node.js hosted version (#820)

# PR Checklist
- ❌ Have you checked if it works normally in all models? *Ignore this if
it doesn't use models.*
   - Not applicable
- ✅ Have you checked if it works normally in all web, local, and node
hosted versions? If it doesn't, have you blocked it in those versions?
   - Done
- ❌ Have you added type definitions?
   - Not applicable

# Description

In the previous commit, a new proxy endpoint was added to the backend to
resolve CORS errors that occurred when the frontend directly fetched
data from Risu Realm.

However, 403 errors were occurring because the POST requests sent from
the loadRisuAccountData() function in the frontend were not being
properly processed.
Additionally, the backend was inefficiently handling complex body
processing.

The updated backend code now provides a more efficient and stable
solution by directly piping the original request.

Furthermore, an issue where UserSettings.svelte couldn't handle tokens
received through the backend proxy after successfully logging into a
Risu account has also been fixed.

src/lib/Others/AlertComp.svelte

@@ -72,7 +72,7 @@
 </script>
 
 <svelte:window onmessage={async (e) => {
-    if(e.origin.startsWith("https://sv.risuai.xyz") || e.origin.startsWith("http://127.0.0.1")){
+    if(e.origin.startsWith("https://sv.risuai.xyz") || e.origin.startsWith("http://127.0.0.1") || e.origin === window.location.origin){
         if(e.data.msg.data.vaild && $alertStore.type === 'login'){
             $alertStore = {
                 type: 'none',

src/lib/Setting/Pages/UserSettings.svelte

@@ -19,7 +19,7 @@
 </script>
 
 <svelte:window onmessage={async (e) => {
-    if(e.origin.startsWith("https://sv.risuai.xyz") || e.origin.startsWith("http://127.0.0.1")){
+    if(e.origin.startsWith("https://sv.risuai.xyz") || e.origin.startsWith("http://127.0.0.1") || e.origin === window.location.origin){
         if(e.data.msg.type === 'drive'){
             await loadRisuAccountData()
             DBState.db.account.data.refresh_token = e.data.msg.data.refresh_token