Fix: Create data directory before initializing search database

Ensures the data directory exists before attempting to open the SQLite database
during Docker image build. This fixes SQLITE_CANTOPEN error during build-search-index.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

backend/src/searchDatabase.js

@@ -1,6 +1,7 @@
 const sqlite3 = require('sqlite3').verbose();
 const path = require('path');
 const fs = require('fs').promises;
+const fsSync = require('fs');
 
 class SearchDatabase {
   constructor(dbPath) {
@@ -10,6 +11,13 @@ class SearchDatabase {
 
   // Initialize database connection
   async initialize() {
+    // Ensure data directory exists
+    const dataDir = path.dirname(this.dbPath);
+    if (!fsSync.existsSync(dataDir)) {
+      fsSync.mkdirSync(dataDir, { recursive: true });
+      console.log('Created data directory:', dataDir);
+    }
+
     return new Promise((resolve, reject) => {
       this.db = new sqlite3.Database(this.dbPath, (err) => {
         if (err) {