Stabilize search pipeline and improve preview diagnostics

frontend/app.js

@@ -68,12 +68,36 @@ function logEvent(type, payload) {
 
 function safeStringify(value) {
   try {
-    return JSON.stringify(value, null, 2);
+    return JSON.stringify(compactPayload(value), null, 2);
   } catch {
     return String(value);
   }
 }
 
+function compactPayload(value, depth = 0) {
+  if (depth > 3) {
+    return "[truncated]";
+  }
+  if (Array.isArray(value)) {
+    if (value.length > 8) {
+      return {
+        type: "array",
+        length: value.length,
+        sample: value.slice(0, 5).map((item) => compactPayload(item, depth + 1)),
+      };
+    }
+    return value.map((item) => compactPayload(item, depth + 1));
+  }
+  if (value && typeof value === "object") {
+    const entries = Object.entries(value);
+    return Object.fromEntries(entries.map(([key, item]) => [key, compactPayload(item, depth + 1)]));
+  }
+  if (typeof value === "string" && value.length > 500) {
+    return `${value.slice(0, 500)}...`;
+  }
+  return value;
+}
+
 function renderLogs() {
   debugSummary.textContent = `${debugEntries.length} events captured`;
   debugLogList.innerHTML = "";
@@ -194,15 +218,24 @@ async function api(path, options = {}) {
     bodyPreview: typeof options.body === "string" ? options.body.slice(0, 800) : "[non-string body]",
   });
   const response = await fetch(path, options);
-  const data = await response.json().catch(() => ({}));
+  const rawText = await response.text();
+  let data = {};
+  if (rawText) {
+    try {
+      data = JSON.parse(rawText);
+    } catch {
+      data = { rawText };
+    }
+  }
   logEvent("api:response", {
     path,
     status: response.status,
     ok: response.ok,
-    body: data,
+    body: compactPayload(data),
   });
   if (!response.ok) {
-    const error = new Error(data.error || "request failed");
+    const message = data.error || data.rawText || `request failed (${response.status})`;
+    const error = new Error(message);
     error.status = response.status;
     error.data = data;
     throw error;
@@ -263,7 +296,8 @@ function renderResults(results) {
     image.src = item.thumbnailUrl || "https://placehold.co/1280x720/0a0a0a/ffffff?text=Preview";
     image.alt = item.title;
     node.querySelector("h3").textContent = item.title;
-    node.querySelector("p").textContent = item.reason;
+    node.querySelector(".result-snippet").textContent = item.snippet || item.reason || item.source || "";
+    node.querySelector(".result-reason").textContent = item.reason ? `AI note: ${item.reason}` : "";
     node.querySelector(".source-badge").textContent = item.source;
     if (item.previewVideoUrl) {
       attachVideoSource(previewVideo, item.previewVideoUrl);