Fix startup report indexing metadata (#44672)

## I have read the
[CONTRIBUTING.md](https://github.com/supabase/supabase/blob/master/CONTRIBUTING.md)
file.

YES

## What kind of change does this PR introduce?

Bug fix and small marketing UI update.

## What is the current behavior?

The 2025 State of Startups page advertises `/state-of-startups` in its
metadata, which can cause Google to prefer the 2026 page for 2025
queries. The 2026 registration page also does not link users or crawlers
back to the 2025 report, and the workspace diff includes an RSS feed
refresh.

## What is the new behavior?

The 2025 page now self-canonicalizes to `/state-of-startups-2025`, the
2026 page has explicit canonical/Open Graph metadata for
`/state-of-startups`, and the registration page now includes a prominent
CTA linking to the 2025 report. This PR also includes the current
`rss.xml` update present in the workspace diff.

## Additional context

No local build or preview was run in this workspace.


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **New Features**
- Added a call-to-action section on the registration page linking to the
State of Startups 2025 report.

- **Chores**
- Improved SEO metadata for State of Startups pages to enhance search
visibility and social media sharing.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

apps/www/app/state-of-startups/page.tsx

@@ -11,6 +11,9 @@ export const metadata: Metadata = SHOW_RESULTS
       title: 'State of Startups 2026 | Supabase',
       description:
         'The latest trends among builders in tech stacks, AI usage, problem domains, and more.',
+      alternates: {
+        canonical: 'https://supabase.com/state-of-startups',
+      },
       openGraph: {
         title: 'State of Startups 2026 | Supabase',
         description:
@@ -26,6 +29,14 @@ export const metadata: Metadata = SHOW_RESULTS
   : {
       title: 'State of Startups 2026 — Survey | Supabase',
       description: 'Be the first to access the State of Startups 2026 report.',
+      alternates: {
+        canonical: 'https://supabase.com/state-of-startups',
+      },
+      openGraph: {
+        title: 'State of Startups 2026 — Survey | Supabase',
+        description: 'Be the first to access the State of Startups 2026 report.',
+        url: 'https://supabase.com/state-of-startups',
+      },
     }
 
 export default function StateOfStartupsPage() {

apps/www/app/state-of-startups/register/RegisterContent.tsx

@@ -134,6 +134,12 @@ export function RegisterContent() {
         <SurveySectionBreak />
       </section>
 
+      <section className="px-4 py-16 md:px-8 md:py-32">
+        <div className="max-w-[60rem] mx-auto">
+          <PreviousResultsCta />
+        </div>
+      </section>
+
       <Footer />
     </main>
   )
@@ -173,3 +179,38 @@ function ShirtImage() {
     </div>
   )
 }
+
+function PreviousResultsCta() {
+  return (
+    <Link
+      href="/state-of-startups-2025"
+      className="group grid gap-8 transition-colors md:grid-cols-[auto_1fr_auto] md:items-end md:gap-12"
+    >
+      <div className="flex w-fit flex-col gap-2" aria-hidden="true">
+        <div className="w-fit bg-brand-300 px-5 py-3 text-[1.75rem] leading-8 tracking-tight text-brand md:text-[2.25rem] md:leading-10">
+          State
+        </div>
+        <div className="w-fit bg-brand-300 px-5 py-3 text-[1.75rem] leading-8 tracking-tight text-brand md:text-[2.25rem] md:leading-10">
+          of
+        </div>
+        <div className="w-fit bg-brand px-5 py-3 text-[1.75rem] leading-8 tracking-tight text-background dark:text-brand-200 md:text-[2.25rem] md:leading-10">
+          Startups
+        </div>
+        <div className="w-fit bg-brand-500 px-5 py-3 text-[1.75rem] leading-8 tracking-tight text-brand-300 md:text-[2.25rem] md:leading-10">
+          2025
+        </div>
+      </div>
+
+      <div className="flex flex-col gap-2 self-end">
+        <p className="font-mono text-xs uppercase tracking-[0.18em] text-foreground-light">
+          Previous Report
+        </p>
+        <p className="text-2xl tracking-tight text-foreground">See last year&apos;s report.</p>
+      </div>
+
+      <div className="flex items-center self-end text-foreground-light transition-transform duration-200 group-hover:translate-x-1 group-hover:text-foreground md:justify-self-end">
+        <ArrowRight size={18} />
+      </div>
+    </Link>
+  )
+}

apps/www/pages/state-of-startups-2025.tsx

@@ -174,10 +174,11 @@ function StateOfStartupsPage() {
       <NextSeo
         title={meta_title}
         description={meta_description}
+        canonical="https://supabase.com/state-of-startups-2025"
         openGraph={{
           title: meta_title,
           description: meta_description,
-          url: `https://supabase.com/state-of-startups`,
+          url: `https://supabase.com/state-of-startups-2025`,
           images: [
             {
               url: `https://supabase.com/images/state-of-startups/state-of-startups-og.png`,