style: complete redo of the email layouts (#20)

utils/extractMainTopic.ts

@@ -0,0 +1,65 @@
+export default function extractMainTopic(summary: string): string {
+  const firstParaMatch = summary.match(/<p>(.*?)<\/p>/);
+  if (!firstParaMatch) return 'tech updates';
+
+  const firstPara = firstParaMatch[1];
+
+  const cleanText = firstPara
+    .replace(/<[^>]*>/g, '')
+    .replace(/\s+/g, ' ')
+    .replace(/[,.]+/g, ' ')
+    .trim();
+
+  const techAreas = [
+    {
+      name: 'AI',
+      pattern: /\b(AI|artificial intelligence|machine learning|ML|GPT|LLM)\b/i,
+      preserveCase: true
+    },
+    {
+      name: 'security',
+      pattern: /\b(security|cyber|hack|privacy|breach)\b/i
+    },
+    {
+      name: 'Web3',
+      pattern: /\b(blockchain|crypto|web3|NFT|token|ethereum|bitcoin)\b/i,
+      preserveCase: true
+    },
+    {
+      name: 'cloud',
+      pattern: /\b(cloud|AWS|Azure|serverless|containerization|kubernetes)\b/i
+    },
+    {
+      name: 'mobile',
+      pattern: /\b(mobile|iOS|Android|app|smartphone)\b/i
+    },
+    {
+      name: 'development',
+      pattern: /\b(developer|programming|code|software|development)\b/i
+    }
+  ];
+
+  for (const area of techAreas) {
+    if (area.pattern.test(cleanText)) {
+      return area.preserveCase ? area.name : area.name.toLowerCase();
+    }
+  }
+
+  const words = cleanText
+    .split(' ')
+    .filter(
+      word =>
+        word.length > 2 &&
+        !/^(and|the|in|of|at|by|for)$/i.test(word) &&
+        !/[,.]/.test(word)
+    )
+    .slice(0, 2)
+    .join(' ');
+
+  const topic = words.toLowerCase() || 'tech updates';
+
+  const titleSuffix =
+    topic === 'tech updates' ? topic : `tech: ${topic} in focus`;
+
+  return `Today in ${titleSuffix}`;
+}