chore(deps): update angular-cli monorepo to v21

Author: renovate[bot]

templates/angular/package.json

@@ -23,8 +23,8 @@
 		"zone.js": "~0.15.1"
 	},
 	"devDependencies": {
-		"@angular/build": "^20.3.10",
-		"@angular/cli": "^20.3.10",
+		"@angular/build": "^21.0.1",
+		"@angular/cli": "^21.0.1",
 		"@angular/compiler-cli": "^20.3.12",
 		"prettier": "^3.6.2",
 		"typescript": "~5.8.3"