Add Discord CTA to ask-supabase-select hero (#51185)

## Problem

The `/go/ask-supabase-select` hero only linked to docs; it didn't point
attendees to Discord.

## Solution

Adds a third hero CTA, "Join our Discord", linking to
`https://discord.supabase.com/`, alongside the existing primary and docs
CTAs.

## Review instructions

1. Run `pnpm --filter www dev` and visit
`http://localhost:3000/go/ask-supabase-select`.
2. Confirm the hero now shows three CTAs and the Discord link works.

## Checklist

- [x] I have read CONTRIBUTING.md

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

* **New Features**
  * Added a “Join our Discord” call to action to the hero section.
* **Updates**
* Updated the three announcement call-to-action links to point to their
respective Supabase Select 2026 blog posts.
* Updated the hero’s “Read the Recap” link to point to the Build
Anything blog post.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Wendie Cheung <wendie.cheung@supabase.io>
Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

apps/www/_go/lead-gen/ask-supabase-select.tsx

@@ -23,21 +23,30 @@ const themes: Theme[] = [
     name: 'Build anything',
     description:
       "Your agent sets up the backend from code, your users' agents work with your app through its own MCP server, and long-running tasks run in Supabase Compute.",
-    cta: { label: 'Read the Build Blog', href: '/docs' },
+    cta: {
+      label: 'Read the Build Blog',
+      href: 'https://supabase.com/blog/select-2026-build-anything',
+    },
     icon: Hammer,
   },
   {
     name: 'Scale without limits',
     description:
       'The app your agent built in minutes stays on the same Postgres, from prototype to petabyte.',
-    cta: { label: 'Read the Scale Blog', href: '/docs' },
+    cta: {
+      label: 'Read the Scale Blog',
+      href: 'https://supabase.com/blog/select-2026-scale-without-limits',
+    },
     icon: Maximize2,
   },
   {
     name: 'Operate with confidence',
     description:
       'Your agent finds the problem, tests the fix, and reports what it found. You decide what ships.',
-    cta: { label: 'Read the Operate Blog', href: '/docs' },
+    cta: {
+      label: 'Read the Operate Blog',
+      href: 'https://supabase.com/blog/select-2026-operate-with-confidence',
+    },
     icon: ShieldCheck,
   },
 ]
@@ -88,9 +97,13 @@ const page: GoPageInput = {
     ctas: [
       {
         label: 'Read the Recap',
-        href: '/docs',
+        href: 'https://supabase.com/blog/select-2026-build-anything',
         variant: 'secondary',
       },
+      {
+        label: 'Join our Discord',
+        href: 'https://discord.supabase.com/',
+      },
     ],
   },
   sections: [