Refactor security scanning and database setup

- Update security scan workflow to utilize a dedicated script for checking secrets, improving detection accuracy.
- Modify database connection setup in multiple scripts to use an environment variable fallback for DATABASE_URL, enhancing flexibility in different environments.

scripts/setup-database.js

@@ -6,7 +6,7 @@ const { exec } = require('child_process');
 console.log('🗄️  Setting up database...');
 
 // Set environment variables for development
-process.env.DATABASE_URL = 'postgresql://portfolio_user:portfolio_dev_pass@localhost:5432/portfolio_dev?schema=public';
+process.env.DATABASE_URL = process.env.DATABASE_URL || 'postgresql://portfolio_user:portfolio_dev_pass@localhost:5432/portfolio_dev?schema=public';
 
 // Function to run command and return promise
 function runCommand(command) {