docs: replace `client-project` in app-shell documentation (#41957)
docs: replace `client-project` in app-shell documentation (#41957)

 This option no longer exists, instead we now point to the `cli/generate#app-shell-command` guide.

PR Close #41957

angular/angular,brandonroberts/angular,gkalpak/angular,JiaLiPassion/angular,gnomeontherun/angular,ocombe/angular,gnomeontherun/angular,shairez/angular,brandonroberts/angular,JiaLiPassion/angular,manekinekko/angular,manekinekko/angular,ocombe/angular,gkalpak/angular,mgechev/angular,manekinekko/angular,brandonroberts/angular,mgechev/angular,mgechev/angular,ocombe/angular,JiaLiPassion/angular,ocombe/angular,shairez/angular,manekinekko/angular,gkalpak/angular,angular/angular,JiaLiPassion/angular,angular/angular,shairez/angular,shairez/angular,ocombe/angular,angular-indonesia/angular,brandonroberts/angular,mgechev/angular,brandonroberts/angular,gnomeontherun/angular,manekinekko/angular,angular-indonesia/angular,shairez/angular,brandonroberts/angular,gkalpak/angular,angular-indonesia/angular,manekinekko/angular,mgechev/angular,angular-indonesia/angular,gnomeontherun/angular,ocombe/angular,angular/angular