⚡ Bolt: [performance improvement] Execute external API requests concurrently in Cloudflare Worker

[Snigdh41]

💡 What: Updated the Cloudflare Worker to execute the independent resend.emails.send requests (notification and auto-reply) concurrently using Promise.all().
🎯 Why: Previously, the auto-reply email request would wait for the notification email request to finish before starting. Since these requests are independent, executing them sequentially accumulates unnecessary latency.
📊 Impact: Reduces the overall API response time for contact submissions by approximately the time it takes to execute the second API request (~50% reduction in email dispatch latency).
🔬 Measurement: Compare the overall response time of the /contact endpoint before and after the change using network profiling or server logs. The overall duration will drop from t(notif) + t(reply) to max(t(notif), t(reply)).

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PR created automatically by Jules for task 4585680858832166439 started by @Snigdh41

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