Surface stream errors/timeouts even when partial content arrived (no more silent truncation)

index.html

@@ -1114,15 +1114,17 @@ async function askModel(prompt, history, onChunk, onStatus){
     if (watchdog) clearTimeout(watchdog);
   }
 
-  if (timedOut && !lastContent){
-    const err = new Error("The streaming connection went quiet for 90 s — likely a backend hang or dropped SSE.");
+  if (timedOut){
+    const err = new Error("The streaming connection went quiet for 90 s — likely a backend hang, dropped SSE, or ZeroGPU duration cap reached.");
     err.title = "Stream timeout";
+    err.partial = lastContent;
     throw err;
   }
-  if (errorPayload && !lastContent){
+  if (errorPayload){
     const err = new Error(errorPayload.message || errorPayload.title || "Backend returned an error.");
     err.title = errorPayload.title;
     err.detail = errorPayload.message;
+    err.partial = lastContent;
     throw err;
   }
   return { answer: lastContent || "The model returned no output. Try again." };
@@ -1407,10 +1409,12 @@ async function sendMessage(text){
     const { answer } = await askModel(text, hist, onChunk, onStatus);
     convo[convo.length - 1] = { role:'bot', text: answer };
   } catch (e){
+    const errMsg = explainError(e);
+    const partial = (e && typeof e.partial === 'string') ? e.partial : '';
     convo[convo.length - 1] = {
       role:'bot',
       error: true,
-      text: explainError(e),
+      text: partial ? `${partial}\n\n— ${errMsg}` : errMsg,
     };
     // Drop the cached gradio Client so the next send rebuilds a fresh
     // SSE/queue connection. If the previous one got into a bad state