security: address assessment findings and bump to v2026.3.11

- C1: Disable Swagger UI in production (env gate)
- M1+M2: Add Helmet.js for security headers (CSP, X-Frame-Options,
  X-Content-Type-Options, Referrer-Policy) and remove X-Powered-By
- H2: Add @nestjs/throttler rate limiting (5 req/min on login/register)
- M4: Remove orgSchema from JWT payload and client-side storage;
  tenant middleware now resolves schema from orgId via cached DB lookup
- L1: Fix Chatwoot user identification (read from auth store on ready)
- Remove schemaName from frontend Organization type and UI displays

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/index.html

@@ -23,6 +23,20 @@
           })
         }
       })(document,"script");
+      window.addEventListener('chatwoot:ready', function() {
+        try {
+          var raw = localStorage.getItem('ledgeriq-auth');
+          if (!raw) return;
+          var auth = JSON.parse(raw);
+          var user = auth && auth.state && auth.state.user;
+          if (user && window.$chatwoot) {
+            window.$chatwoot.setUser(user.id, {
+              name: (user.firstName || '') + ' ' + (user.lastName || ''),
+              email: user.email
+            });
+          }
+        } catch (e) {}
+      });
     </script>
   </body>
 </html>