Added JIRA ticket tracking feature

- New jira_tickets table (migration script included)
- CRUD API endpoints for tickets with validation and audit logging
- Dashboard section showing all open vendor tickets
- JIRA tickets section within CVE vendor cards
- Tickets linked to CVE + vendor with status tracking (Open/In Progress/Closed)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/migrate_jira_tickets.js

@@ -0,0 +1,39 @@
+// Migration: Add jira_tickets table
+const sqlite3 = require('sqlite3').verbose();
+const path = require('path');
+
+const dbPath = path.join(__dirname, 'cve_database.db');
+const db = new sqlite3.Database(dbPath);
+
+console.log('Starting JIRA tickets migration...');
+
+db.serialize(() => {
+  // Create jira_tickets table
+  db.run(`
+    CREATE TABLE IF NOT EXISTS jira_tickets (
+      id INTEGER PRIMARY KEY AUTOINCREMENT,
+      cve_id TEXT NOT NULL,
+      vendor TEXT NOT NULL,
+      ticket_key TEXT NOT NULL,
+      url TEXT,
+      summary TEXT,
+      status TEXT DEFAULT 'Open' CHECK(status IN ('Open', 'In Progress', 'Closed')),
+      created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+      updated_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+      FOREIGN KEY (cve_id, vendor) REFERENCES cves(cve_id, vendor) ON DELETE CASCADE
+    )
+  `, (err) => {
+    if (err) console.error('Error creating table:', err);
+    else console.log('✓ jira_tickets table created');
+  });
+
+  // Create indexes
+  db.run('CREATE INDEX IF NOT EXISTS idx_jira_tickets_cve ON jira_tickets(cve_id, vendor)');
+  db.run('CREATE INDEX IF NOT EXISTS idx_jira_tickets_status ON jira_tickets(status)');
+
+  console.log('✓ Indexes created');
+});
+
+db.close(() => {
+  console.log('Migration complete!');
+});