fix(proxy): modify the registration of the axios interceptors

The previous way of adding Axios interceptors added a new interceptor each time, causing lags after
a while because of all the duplicate interceptors added.

fix #1787

server/routes/imageproxy.ts

@@ -4,40 +4,27 @@ import { Router } from 'express';
 
 const router = Router();
 
-// Delay the initialization of ImageProxy instances until the proxy (if any) is properly configured
-let _tmdbImageProxy: ImageProxy;
-function initTmdbImageProxy() {
-  if (!_tmdbImageProxy) {
-    _tmdbImageProxy = new ImageProxy('tmdb', 'https://image.tmdb.org', {
-      rateLimitOptions: {
-        maxRequests: 20,
-        maxRPS: 50,
-      },
-    });
-  }
-  return _tmdbImageProxy;
-}
-let _tvdbImageProxy: ImageProxy;
-function initTvdbImageProxy() {
-  if (!_tvdbImageProxy) {
-    _tvdbImageProxy = new ImageProxy('tvdb', 'https://artworks.thetvdb.com', {
-      rateLimitOptions: {
-        maxRequests: 20,
-        maxRPS: 50,
-      },
-    });
-  }
-  return _tvdbImageProxy;
-}
+const tmdbImageProxy = new ImageProxy('tmdb', 'https://image.tmdb.org', {
+  rateLimitOptions: {
+    maxRequests: 20,
+    maxRPS: 50,
+  },
+});
+const tvdbImageProxy = new ImageProxy('tvdb', 'https://artworks.thetvdb.com', {
+  rateLimitOptions: {
+    maxRequests: 20,
+    maxRPS: 50,
+  },
+});
 
 router.get('/:type/*', async (req, res) => {
   const imagePath = req.path.replace(/^\/\w+/, '');
   try {
     let imageData;
     if (req.params.type === 'tmdb') {
-      imageData = await initTmdbImageProxy().getImage(imagePath);
+      imageData = await tmdbImageProxy.getImage(imagePath);
     } else if (req.params.type === 'tvdb') {
-      imageData = await initTvdbImageProxy().getImage(imagePath);
+      imageData = await tvdbImageProxy.getImage(imagePath);
     } else {
       logger.error('Unsupported image type', {
         imagePath,