fix: retry aiguoguo /images/generations once on 5xx (12s delay)

src/services/covers.js

@@ -357,10 +357,22 @@ async function generateCover({ articleId, title, tags = [], channelId = null })
   let img;
   let usedPath = 'images-generations';
 
-  // Цепочка: 1) aiguoguo /images/generations → 2) aiprimetech /responses → 3) legacy → 4) local SVG
+  // Цепочка: 1) aiguoguo /images/generations (2 попытки) → 2) aiprimetech /responses → 3) legacy → 4) local SVG
   try {
     try {
-      img = await generateCoverViaImageGenerations({ prompt });
+      try {
+        img = await generateCoverViaImageGenerations({ prompt });
+      } catch (err) {
+        // Ретрай только при временных ошибках провайдера (5xx)
+        const status = err.response?.status;
+        if (status >= 500 && status < 600) {
+          console.warn(`[Cover] /images/generations ${status} — retry in 12s...`);
+          await new Promise(r => setTimeout(r, 12000));
+          img = await generateCoverViaImageGenerations({ prompt });
+        } else {
+          throw err;
+        }
+      }
     } catch (err) {
       console.warn(`[Cover] /images/generations failed: ${(err.response?.data?.error?.message || err.message).slice(0, 150)}`);
       try {