Upgrade Angular 21

[phongnguyend]

https://angular.dev/update-guide?v=20.0-21.0&l=1

npm uninstall -g @angular/cli
npm install -g @angular/cli@latest

npm outdated
npm audit --audit-level=high
ng update
ng update @angular/core@21 @angular/cli@21 @ngrx/store
ng update
npm audit fix

Blockers:

• Add support for Angular 21 valor-software/ngx-bootstrap#6787
• PSA: Angular v21 and NgRx v21 ngrx/platform#5005