Add search result snippet highlighting and database query timeout enforcement

src/config/database-timeout.config.ts

@@ -0,0 +1,4 @@
+export const databaseTimeoutConfig = {
+  statementTimeout: Number(process.env.DB_STATEMENT_TIMEOUT_MS) || 30000,
+  slowQueryThreshold: Number(process.env.DB_SLOW_QUERY_THRESHOLD_MS) || 1000,
+};

src/search/services/snippet.service.ts

@@ -0,0 +1,22 @@
+import { Injectable } from '@nestjs/common';
+
+@Injectable()
+export class SnippetService {
+  generateSnippet(text: string, query: string): string {
+    const lower = text.toLowerCase();
+    const idx = lower.indexOf(query.toLowerCase());
+    if (idx === -1) return text.substring(0, 200);
+
+    const start = Math.max(0, idx - 50);
+    const end = Math.min(text.length, idx + query.length + 150);
+    let snippet = text.substring(start, end);
+
+    const escapedQuery = query.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+    const regex = new RegExp(`(${escapedQuery})`, 'gi');
+    snippet = snippet.replace(regex, '<mark>$1</mark>');
+
+    if (start > 0) snippet = `...${snippet}`;
+    if (end < text.length) snippet = `${snippet}...`;
+    return snippet;
+  }
+}