Reduce scan terminal origin load

frontend/app/api/scan/terminal/route.ts

@@ -1,6 +1,7 @@
 import { NextRequest, NextResponse } from "next/server";
 import { proxyBackendJsonGet } from "@/lib/api-proxy";
 import { buildForceRefreshProxyCachePolicy } from "@/lib/proxy-cache-policy";
+import { DASHBOARD_REFRESH_POLICY_SEC } from "@/lib/refresh-policy";
 
 const API_BASE = process.env.POLYWEATHER_API_BASE_URL;
 const SCAN_TERMINAL_PROXY_TIMEOUT_MS = Number(
@@ -41,7 +42,10 @@ export async function GET(req: NextRequest) {
   if (tradingRegion != null && tradingRegion !== "") {
     params.set("region", tradingRegion);
   }
-  const cachePolicy = buildForceRefreshProxyCachePolicy(forceRefresh, 10);
+  const cachePolicy = buildForceRefreshProxyCachePolicy(
+    forceRefresh,
+    DASHBOARD_REFRESH_POLICY_SEC.scanRows,
+  );
 
   const url = `${API_BASE}/api/scan/terminal?${params.toString()}`;
 

frontend/components/dashboard/scan-terminal/__tests__/proxyCachePolicy.test.ts

@@ -25,6 +25,37 @@ export function runTests() {
   const scanForced = buildForceRefreshProxyCachePolicy("true", 10);
   assert.equal(scanForced.fetchMode, "no-store");
 
+  const scanTerminalProxySource = fs.readFileSync(
+    path.join(process.cwd(), "app", "api", "scan", "terminal", "route.ts"),
+    "utf8",
+  );
+  assert.match(
+    scanTerminalProxySource,
+    /DASHBOARD_REFRESH_POLICY_SEC\.scanRows/,
+    "scan terminal proxy cache TTL should match the dashboard scan refresh cadence instead of a short literal TTL",
+  );
+  assert.doesNotMatch(
+    scanTerminalProxySource,
+    /buildForceRefreshProxyCachePolicy\(forceRefresh,\s*10\)/,
+    "scan terminal proxy must not use the old 10 second edge cache because it over-drives the slow scan endpoint",
+  );
+
+  const scanTerminalClientSource = fs.readFileSync(
+    path.join(
+      process.cwd(),
+      "components",
+      "dashboard",
+      "scan-terminal",
+      "scan-terminal-client.ts",
+    ),
+    "utf8",
+  );
+  assert.match(
+    scanTerminalClientSource,
+    /hasDirectBackendApiBaseUrl/,
+    "public scan terminal requests should only attach user auth in direct-backend mode so CDN caches can be shared through the Next proxy",
+  );
+
   const overviewProxySource = fs.readFileSync(
     path.join(
       process.cwd(),

frontend/components/dashboard/scan-terminal/scan-terminal-client.ts

@@ -3,6 +3,7 @@
 import {
   buildBrowserBackendHeaders,
   fetchBackendApi,
+  hasDirectBackendApiBaseUrl,
 } from "@/lib/backend-api";
 import { DASHBOARD_REFRESH_POLICY_MS } from "@/lib/refresh-policy";
 import type {
@@ -144,11 +145,14 @@ async function getTerminal({
   if (forceRefresh) {
     params.set("_ts", String(Date.now()));
   }
-  const headers = await buildBrowserBackendHeaders({ Accept: "application/json" });
+  const directBackend = hasDirectBackendApiBaseUrl();
+  const headers = directBackend
+    ? await buildBrowserBackendHeaders({ Accept: "application/json" })
+    : new Headers({ Accept: "application/json" });
   return readJsonOrThrow<ScanTerminalResponse>(
     `/api/scan/terminal?${params.toString()}`,
     {
-      cache: "no-store",
+      cache: forceRefresh || directBackend ? "no-store" : "default",
       headers,
       signal,
     },