fix: make /releases route public (no auth required)

Added /releases to publicRoutes in middleware to allow
unauthenticated access to feature documentation.

The documentation pages are part of the build-in-public
approach and should be accessible to everyone.

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

Co-Authored-By: Claude <noreply@anthropic.com>

middleware.ts

@@ -50,6 +50,7 @@ export async function middleware(request: NextRequest) {
     '/update-password',
     '/auth/callback',
     '/contact',
+    '/releases',
     '/api/leads',
     '/robots.txt',
     '/sitemap.xml',