Use YEAR in hack/boilerplate.go.txt as a literal for the current year

The YEAR string in the boilerplate header file will be replaced by
controller-gen[^1] and kubebuilder[^2].

This change also requires to define a YEAR variable in the Makefile
(holding the current year) which is passed as year=$(YEAR) to the
controller-gen crd generation. The applyconfiguration generator of
controller-gen handles this substitution automatically by using
kubernetes/gengo[^3] and does not need the explicit parameter.

[^1]: kubernetes-sigs/controller-tools@54a2e9f
[^2]: kubernetes-sigs/kubebuilder@890b118
[^3]: https://github.com/kubernetes/gengo/blob/5ee0d033ba5bcb073f0e69c32057520b82d75ccb/v2/execute.go#L59

Author: felix-kaestner

Makefile

@@ -256,14 +256,15 @@ GO_COVERPKGS := $(shell go list ./... | grep -E '/internal')
 null :=
 space := $(null) $(null)
 comma := ,
+YEAR ?= $(shell date +%Y)
 
 check: FORCE static-check build/cover.html build-all
 	@printf "\e[1;32m>> All checks successful.\e[0m\n"
 
 generate: install-controller-gen
 	@printf "\e[1;36m>> controller-gen\e[0m\n"
 	@controller-gen crd rbac:roleName=manager-role webhook paths="./..." output:crd:artifacts:config=config/crd/bases
-	@controller-gen object:headerFile="hack/boilerplate.go.txt" paths="./..."
+	@controller-gen object:headerFile="hack/boilerplate.go.txt",year=$(YEAR) paths="./..."
 	@controller-gen applyconfiguration:headerFile="hack/boilerplate.go.txt" paths="./..."
 
 run-golangci-lint: FORCE install-golangci-lint
@@ -343,6 +344,7 @@ vars: FORCE
 	@printf "SED=$(SED)\n"
 	@printf "UNAME_S=$(UNAME_S)\n"
 	@printf "XARGS=$(XARGS)\n"
+	@printf "YEAR=$(YEAR)\n"
 help: FORCE
 	@printf "\n"
 	@printf "\e[1mUsage:\e[0m\n"

api/cisco/nx/v1alpha1/zz_generated.deepcopy.go

@@ -1,2 +1,2 @@
-// SPDX-FileCopyrightText: 2025 SAP SE or an SAP affiliate company and IronCore contributors
+// SPDX-FileCopyrightText: YEAR SAP SE or an SAP affiliate company and IronCore contributors
 // SPDX-License-Identifier: Apache-2.0