fix(routing): serialize route updates and correct VPN-gated route application

ts/vpn/classes.vpn-manager.ts

@@ -267,7 +267,18 @@ export class VpnManager {
       doc.vlanId = opts.vlanId;
     }
     this.clients.set(doc.clientId, doc);
-    await this.persistClient(doc);
+    try {
+      await this.persistClient(doc);
+    } catch (err) {
+      // Rollback: remove from in-memory map and daemon to stay consistent with DB
+      this.clients.delete(doc.clientId);
+      try {
+        await this.vpnServer!.removeClient(doc.clientId);
+      } catch {
+        // best-effort daemon cleanup
+      }
+      throw err;
+    }
 
     // Sync per-client security to the running daemon
     const security = this.buildClientSecurity(doc);