⚡ Bolt: Use Promise.all for concurrent email sending

[Snigdh41]

💡 What: Replaced sequential resend.emails.send calls with Promise.all() in the contact API worker, and converted the Next.js <a> tag in Navbar to <Link> for prefetching and client-side routing.
🎯 Why: To reduce latency in the contact worker (the notification and auto-reply emails can be sent at the same time), and to improve Next.js performance by avoiding full page reloads.
📊 Impact: Reduces the overall execution time of the worker handling the /contact route, and provides seamless client-side navigation.
🔬 Measurement: Test the contact form submission on the frontend or hit the /contact API endpoint to observe reduced response time. Check client-side navigation speed when clicking the site logo.

---

PR created automatically by Jules for task 17823757849830429983 started by @Snigdh41

[google-labs-jules]

👋 Jules, reporting for duty! I'm here to lend a hand with this pull request.

When you start a review, I'll add a 👀 emoji to each comment to let you know I've read it. I'll focus on feedback directed at me and will do my best to stay out of conversations between you and other bots or reviewers to keep the noise down.

I'll push a commit with your requested changes shortly after. Please note there might be a delay between these steps, but rest assured I'm on the job!

For more direct control, you can switch me to Reactive Mode. When this mode is on, I will only act on comments where you specifically mention me with @jules. You can find this option in the Pull Request section of your global Jules UI settings. You can always switch back!

New to Jules? Learn more at jules.google/docs.

---

For security, I will only act on instructions from the user who triggered this task.