treewide: add license header and enable haslicense linter

Change-Id: I873a8d4082d75e8f813d8a726a41187eea7a065e
Reviewed-on: https://review.monogon.dev/c/monogon/+/3825
Tested-by: Jenkins CI
Reviewed-by: Leopold Schabel <leo@monogon.tech>
diff --git a/metropolis/node/core/mgmt/mgmt.go b/metropolis/node/core/mgmt/mgmt.go
index b0632bb..78961f2 100644
--- a/metropolis/node/core/mgmt/mgmt.go
+++ b/metropolis/node/core/mgmt/mgmt.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 // Package mgmt implements the node-local management service, a.k.a.
 // metropolis.proto.api.NodeManagement.
 package mgmt
diff --git a/metropolis/node/core/mgmt/power.go b/metropolis/node/core/mgmt/power.go
index 9273ab3..6a3a8f2 100644
--- a/metropolis/node/core/mgmt/power.go
+++ b/metropolis/node/core/mgmt/power.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package mgmt
 
 import (
diff --git a/metropolis/node/core/mgmt/svc_logs.go b/metropolis/node/core/mgmt/svc_logs.go
index 6e27bf8..7a6ded5 100644
--- a/metropolis/node/core/mgmt/svc_logs.go
+++ b/metropolis/node/core/mgmt/svc_logs.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package mgmt
 
 import (
diff --git a/metropolis/node/core/mgmt/svc_logs_test.go b/metropolis/node/core/mgmt/svc_logs_test.go
index e91d2a3..f778084 100644
--- a/metropolis/node/core/mgmt/svc_logs_test.go
+++ b/metropolis/node/core/mgmt/svc_logs_test.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package mgmt
 
 import (
diff --git a/metropolis/node/core/mgmt/update.go b/metropolis/node/core/mgmt/update.go
index 6a7e13e..de9b876 100644
--- a/metropolis/node/core/mgmt/update.go
+++ b/metropolis/node/core/mgmt/update.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package mgmt
 
 import (