feat: /speedtest-rpc browser RPC speed test

src/app/rpc/page.tsx

@@ -158,6 +158,19 @@ export default async function RpcHubPage() {
         </div>
       </header>
 
+      <section className="mb-8 rounded-lg border border-ink/10 card-soft px-4 py-3 flex items-start gap-3">
+        <span className="mt-0.5 inline-block w-2 h-2 rounded-full shrink-0" style={{ background: "var(--color-good)" }} aria-hidden />
+        <p className="text-sm text-ink leading-snug">
+          Want these numbers from <em>your</em> connection?{" "}
+          <Link href="/speedtest-rpc" className="font-semibold underline underline-offset-2">
+            Run the browser RPC speed test →
+          </Link>{" "}
+          <span className="text-ink-faint">
+            Paste any endpoints (keyed included), no install, URLs never leave your browser.
+          </span>
+        </p>
+      </section>
+
       {keyedRpcSpecs.length > 0 && (
         <section className="mb-8 rounded-lg border border-ink/10 card-soft px-4 py-3">
           <p className="label-mono text-[10px] text-ink-faint mb-2">

src/app/speedtest-rpc/page.tsx

@@ -0,0 +1,95 @@
+import type { Metadata } from "next";
+import Link from "next/link";
+import { pageMetadata } from "@/lib/page-metadata";
+import { SpeedtestRpcClient } from "@/components/speedtest/speedtest-rpc-client";
+import { buildBreadcrumbJsonLd, safeJsonLd } from "@/lib/jsonld";
+import { SITE } from "@/data/site";
+
+export const metadata: Metadata = pageMetadata({
+  path: "/speedtest-rpc",
+  title: "RPC Speed Test — benchmark your endpoints from your browser",
+  description:
+    "Paste any RPC URLs and measure their real latency from your own connection. Same anti-cache methodology as our public benchmarks. No install, no signup — your URLs and API keys never leave your browser.",
+});
+
+export const revalidate = 3600;
+
+export default function SpeedtestRpcPage() {
+  const jsonLd = {
+    "@context": "https://schema.org",
+    "@graph": [
+      buildBreadcrumbJsonLd([
+        { name: "Home", item: SITE.url },
+        { name: "RPC Speed Test", item: `${SITE.url}/speedtest-rpc` },
+      ]),
+      {
+        "@type": "WebApplication",
+        "@id": `${SITE.url}/speedtest-rpc#app`,
+        name: "RPC Speed Test",
+        url: `${SITE.url}/speedtest-rpc`,
+        applicationCategory: "DeveloperApplication",
+        operatingSystem: "Web",
+        offers: { "@type": "Offer", price: "0", priceCurrency: "USD" },
+        description:
+          "Browser-based latency test for JSON-RPC endpoints. Probes run directly from the visitor's connection with the same anti-cache methodology as OpenChainBench's public benchmarks; endpoint URLs never reach OpenChainBench servers.",
+        publisher: { "@id": `${SITE.url}/#org` },
+      },
+    ],
+  };
+
+  return (
+    <article className="mx-auto max-w-[840px] px-4 sm:px-6 py-10 sm:py-14">
+      <script
+        type="application/ld+json"
+        // biome-ignore lint/security/noDangerouslySetInnerHtml: serialized via safeJsonLd
+        dangerouslySetInnerHTML={{ __html: safeJsonLd(jsonLd) }}
+      />
+      <p className="font-sans text-[11px] uppercase tracking-[0.18em] text-ink-faint mb-3">
+        RPC speed test
+      </p>
+      <h1 className="display text-3xl sm:text-5xl text-ink leading-[1.05]">
+        Benchmark your RPC endpoints, from your connection
+      </h1>
+      <p className="mt-4 max-w-2xl text-base sm:text-lg text-ink-soft leading-snug">
+        Paste any JSON-RPC URLs — public gateways or your own keyed endpoints —
+        pick a duration, and watch them race. Every probe fires directly from
+        your browser with the same anti-cache payload as our{" "}
+        <Link href="/rpc" className="lnk">
+          public RPC benchmarks
+        </Link>
+        , so the numbers are comparable to the leaderboards.
+      </p>
+      <p className="mt-2 text-sm text-ink-faint">
+        No install, no signup. Your URLs and API keys never leave this browser
+        tab — requests go straight from you to the provider.
+      </p>
+
+      <SpeedtestRpcClient />
+
+      <section className="mt-14 border-t border-rule pt-6 text-[13px] text-ink-soft leading-relaxed max-w-2xl">
+        <p className="label-mono text-[10px] uppercase tracking-[0.2em] text-ink-faint mb-3">
+          Methodology
+        </p>
+        <p>
+          Each endpoint receives an identical{" "}
+          <code className="font-mono text-[12px]">
+            eth_getBlockByNumber(&quot;latest&quot;, false)
+          </code>{" "}
+          POST with a rotating request id, so no edge cache can answer without
+          touching a real node. One warmup request absorbs the TCP + TLS
+          handshake, then endpoints are probed in randomized round-robin order
+          until the clock runs out — network wake-ups hit every endpoint
+          evenly. Responses are classified ok / http_err / jsonrpc_err /
+          timeout, and an endpoint reporting a block more than 20 behind the
+          best tip in the same round is flagged stale. Latency percentiles use
+          ok responses only, exactly like the{" "}
+          <Link href="/methodology" className="lnk">
+            public benchmark methodology
+          </Link>
+          . Results reflect your device, network and location — that is the
+          point: it is the latency your application would actually see.
+        </p>
+      </section>
+    </article>
+  );
+}