Add Archer Risk Acceptance Tickets feature

- Add archer_tickets table with EXC number, Archer URL, status, CVE, and vendor
- Create backend routes for CRUD operations on Archer tickets
- Add right panel section displaying active Archer tickets
- Implement modals for creating and editing Archer tickets
- Validate EXC number format (EXC-XXXX)
- Support statuses: Draft, Open, Under Review, Accepted
- Purple theme (#8B5CF6) to distinguish from JIRA tickets
- Role-based access control for create/edit/delete operations

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

backend/routes/archerTickets.js

@@ -1,8 +1,17 @@
 // routes/archerTickets.js
 const express = require('express');
 const { requireAuth, requireRole } = require('../middleware/auth');
-const { isValidCveId, isValidVendor } = require('../helpers/validators');
-const { logAudit } = require('../helpers/auditHelpers');
+const logAudit = require('../helpers/auditLog');
+
+// Validation helpers
+const CVE_ID_PATTERN = /^CVE-\d{4}-\d{4,}$/;
+function isValidCveId(cveId) {
+  return typeof cveId === 'string' && CVE_ID_PATTERN.test(cveId);
+}
+
+function isValidVendor(vendor) {
+  return typeof vendor === 'string' && vendor.trim().length > 0 && vendor.length <= 200;
+}
 
 function createArcherTicketsRouter(db) {
   const router = express.Router();