feat(tools): add batch email sending utility

tools/promotional-emails.js

@@ -0,0 +1,73 @@
+const fs = require('fs');
+const path = require('path');
+const { Resend } = require('resend');
+require('dotenv').config();
+
+const resend = new Resend(
+    process.env.RESEND_API_KEY_2 ||
+    process.env.RESEND_API_KEY
+);
+
+const BATCH_SIZE = 100;
+
+async function sendEmail(email) {
+    return resend.emails.send({
+          from: process.env.EMAIL_FROM || 'urBackend <urbackend@apps.bitbros.in>',
+        to: email,
+        subject: 'Try urBackend',
+        html: `
+            <h2>Hi there 👋</h2>
+
+            <p>I'm building urBackend, an open-source backend platform that helps developers build APIs and backend services faster.</p>
+
+            <p>I'd love for you to try it out and share feedback.</p>
+
+            <p>
+                <a href="https://urbackend.bitbros.in">
+                    Try urBackend
+                </a>
+            </p>
+
+            <p>Thanks!</p>
+        `
+    });
+}
+
+async function main() {
+    const emails = fs
+        .readFileSync(
+            path.join(__dirname, 'emails.txt'),
+            'utf8'
+        )
+        .split(/\r?\n/)
+        .map(e => e.trim())
+        .filter(Boolean);
+
+     const parsed = Number(process.argv[2]);
+   const batchSize = Number.isInteger(parsed) && parsed > 0 ? parsed : BATCH_SIZE;
+    const batch = emails.slice(0, Math.min(batchSize, emails.length));
+    console.log(`Sending ${batch.length} emails...`);
+
+     const redactEmail = (value) => {
+       const [local, domain] = String(value).split('@');
+        if (!domain) return '***';
+        return `${local?.slice(0, 2) || '**'}***@${domain}`;
+    };
+
+    for (const email of batch) {
+        try {
+            await sendEmail(email);
+          console.error(`✗ ${redactEmail(email)}`, err.message);
+            await new Promise(resolve =>
+                setTimeout(resolve, 1000)
+            );
+
+        } catch (err) {
+             console.error(`✗ ${redactEmail(email)}`, err.message);
+        }
+    }
+
+    console.log('Finished');
+}
+
+main();