feat(postgres): infrastructure setup and schema creation (tasks 1-2)

- Install pg (node-postgres) dependency
- Create backend/db.js connection pool module (max 10, auto-reconnect)
- Install Docker and spin up steam-postgres container on port 5433
- Create backend/db-schema.sql with complete Postgres DDL (24 tables)
- Replace findings_json blob with ivanti_findings table (individual rows)
- Merge notes/overrides into findings table columns
- Add proper indexes: state, bu_ownership, severity, composite
- Create backend/setup-postgres.js for idempotent schema initialization
- Add DATABASE_URL to .env and .env.example
- Update migration plan docs with Docker setup commands
- Verify: schema executes cleanly, pool connects, 24 tables created

backend/setup-postgres.js

@@ -0,0 +1,49 @@
+// Setup Script for CVE Dashboard — PostgreSQL
+// Runs the db-schema.sql DDL against the Postgres instance configured in DATABASE_URL.
+// Idempotent — safe to run multiple times.
+//
+// Usage: node backend/setup-postgres.js
+//
+// Requires DATABASE_URL in .env or environment.
+
+require('dotenv').config({ path: require('path').join(__dirname, '.env') });
+
+const fs = require('fs');
+const path = require('path');
+const pool = require('./db');
+
+const SCHEMA_FILE = path.join(__dirname, 'db-schema.sql');
+
+async function main() {
+    console.log('🚀 CVE Dashboard — PostgreSQL Schema Setup\n');
+    console.log('════════════════════════════════════════\n');
+
+    try {
+        // Verify connection
+        const { rows } = await pool.query('SELECT version()');
+        console.log(`✓ Connected to: ${rows[0].version.split(',')[0]}`);
+        console.log(`  Database URL: ${process.env.DATABASE_URL.replace(/:[^:@]+@/, ':***@')}\n`);
+
+        // Read and execute schema
+        const schema = fs.readFileSync(SCHEMA_FILE, 'utf8');
+        await pool.query(schema);
+        console.log('✓ Schema created/verified (all tables and indexes)\n');
+
+        // Verify table count
+        const { rows: tables } = await pool.query(
+            "SELECT COUNT(*) as count FROM information_schema.tables WHERE table_schema = 'public'"
+        );
+        console.log(`✓ ${tables[0].count} tables in database\n`);
+
+        console.log('╔════════════════════════════════════════════════════════╗');
+        console.log('║       POSTGRESQL SCHEMA SETUP COMPLETE                 ║');
+        console.log('╚════════════════════════════════════════════════════════╝\n');
+    } catch (err) {
+        console.error('❌ Setup failed:', err.message);
+        process.exit(1);
+    } finally {
+        await pool.end();
+    }
+}
+
+main();