BindTSIGKey: add secretTemplate for labels/annotations on the managed Secret

The operator-generated TSIG Secret previously carried only the managed-by
label, so it could not be mirrored to another namespace by emberstack
reflector (which requires reflection-allowed annotations on the source).

Add spec.secretTemplate.{annotations,labels}, applied both when the Secret
is first generated and reconciled onto the existing Secret when the CR
changes (imported secrets are left untouched so we don't fight their
external manager). This lets the external-dns TSIG key be managed in
bind-internal and reflected into the externaldns namespace.

go.mod

@@ -3,6 +3,7 @@ module git.unkin.net/unkin/bind-operator
 go 1.25
 
 require (
+	github.com/go-logr/logr v1.4.2
 	k8s.io/api v0.34.4
 	k8s.io/apimachinery v0.34.4
 	k8s.io/client-go v0.34.4
@@ -17,7 +18,6 @@ require (
 	github.com/evanphx/json-patch/v5 v5.9.11 // indirect
 	github.com/fsnotify/fsnotify v1.9.0 // indirect
 	github.com/fxamacker/cbor/v2 v2.9.0 // indirect
-	github.com/go-logr/logr v1.4.2 // indirect
 	github.com/go-logr/zapr v1.3.0 // indirect
 	github.com/go-openapi/jsonpointer v0.21.0 // indirect
 	github.com/go-openapi/jsonreference v0.20.2 // indirect