fix: preview cannot be loaded in exhentai mode

app/src/main/java/com/hippo/ehviewer/client/EhCacheKeyFactory.kt

@@ -24,7 +24,7 @@ import com.hippo.ehviewer.client.data.NormalGalleryPreview
 // EHentai Large Preview: https://ehgt.org/***
 
 private const val URL_PREFIX_THUMB_E = "https://ehgt.org/"
-private const val URL_PREFIX_THUMB_EX = "https://exhentai.org/"
+private const val URL_PREFIX_THUMB_EX = "https://s.exhentai.org/"
 
 fun getImageKey(gid: Long, index: Int): String {
     return "image:$gid:$index"

app/src/main/java/com/hippo/ehviewer/client/EhDns.kt

@@ -56,6 +56,13 @@ object EhDns : Dns {
             Pair("178.175.132.20", false),
             Pair("178.175.132.22", false),
         )
+        put(
+            builtInHosts,
+            "s.exhentai.org",
+            Pair("178.175.129.254", false),
+            Pair("178.175.128.254", false),
+            Pair("178.175.132.22", false),
+        )
         put(
             builtInHosts,
             "repo.e-hentai.org",