Let TerdutServer customize its pod, and never manage its own ingress

spec.pod (api/v1alpha1/terdutserver_types.go): annotations, nodeSelector,
tolerations, affinity, topologySpreadConstraints, resources, pod and
container securityContext, serviceAccountName, extraEnv/extraEnvFrom,
extraVolumes/extraVolumeMounts, imagePullSecrets, and an optional
disruptionBudget. All direct corev1 passthrough -- no wrapper types buy
anything for any of these, matching how CloudNativePG and the Zalando
postgres-operator both expose the same knobs, and matching this repo's
own SweeperSpec precedent ("wrap only when a round-trip through a
different type buys something"). affinity is pure user-supplied
passthrough, not a toggle-plus-generated-default the way a multi-replica
cluster operator's pod anti-affinity usually is: this operator never
auto-generates one, since spec.replicas above 1 isn't a supported
topology (the sweeper/notifier singleton constraint). Considered and
declined for this round: priorityClassName, pod labels beyond
annotations, and a HorizontalPodAutoscaler -- the last of those would
directly contradict the singleton constraint above.

disruptionBudget is the one field here that isn't a plain PodTemplateSpec
knob: when set, the controller now reconciles a PodDisruptionBudget
selecting the TerdutServer's own pods (new terdutserver_pdb.go); clearing
it deletes any it previously created. New RBAC marker on
poddisruptionbudgets to match.

Driven by a public-release pass: looking past this project's own use case
at what a mature, general-purpose operator CRD exposes here (researched
against Zalando postgres-operator and CloudNativePG specifically), not
just the fields this install happened to need.

Separately, and found while answering a question about exposing
TerdutServer through Istio instead of Gateway API: spec.networking's own
doc comment quietly promised a Gateway API HTTPRoute this operator would
build eventually ("a near-term follow-up, not deferred"). That promise is
wrong for a public release -- an operator managing someone's ingress
mechanism for them is a worse default than not touching it at all, and a
surprise HTTPRoute appearing once that follow-up eventually landed would
have been exactly backwards for an Istio (or plain-Ingress, or
intentionally-unexposed) install. Made the non-goal explicit and
permanent instead (DESIGN.md §1), removed the dead `gatewayListener`
field it was the only consumer of (zero runtime call sites anywhere --
setting it already had no effect, so this is a schema cleanup, not a
behavior change), and corrected ROADMAP.md's framing. hostname/servicePort
stay: both are live (TERDUT_PUBLIC_URL, container/Service port), this
operator just never acts on hostname for exposure. Added
examples/networking (Gateway API HTTPRoute, Istio VirtualService) showing
how to expose the plain ClusterIP Service the operator already creates --
outside the operator itself, as illustrations, not as something
examples/demo applies automatically.

No new terdut-server version requirement: both changes are CRD/controller-
only, nothing about the API this operator's bootstrap flow depends on
changed.

api/v1alpha1/zz_generated.deepcopy.go

@@ -5,8 +5,10 @@
 package v1alpha1
 
 import (
+	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/util/intstr"
 )
 
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
@@ -210,6 +212,128 @@ func (in *OIDCSpec) DeepCopy() *OIDCSpec {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *PodDisruptionBudgetSpec) DeepCopyInto(out *PodDisruptionBudgetSpec) {
+	*out = *in
+	if in.MinAvailable != nil {
+		in, out := &in.MinAvailable, &out.MinAvailable
+		*out = new(intstr.IntOrString)
+		**out = **in
+	}
+	if in.MaxUnavailable != nil {
+		in, out := &in.MaxUnavailable, &out.MaxUnavailable
+		*out = new(intstr.IntOrString)
+		**out = **in
+	}
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new PodDisruptionBudgetSpec.
+func (in *PodDisruptionBudgetSpec) DeepCopy() *PodDisruptionBudgetSpec {
+	if in == nil {
+		return nil
+	}
+	out := new(PodDisruptionBudgetSpec)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *PodSpec) DeepCopyInto(out *PodSpec) {
+	*out = *in
+	if in.Annotations != nil {
+		in, out := &in.Annotations, &out.Annotations
+		*out = make(map[string]string, len(*in))
+		for key, val := range *in {
+			(*out)[key] = val
+		}
+	}
+	if in.NodeSelector != nil {
+		in, out := &in.NodeSelector, &out.NodeSelector
+		*out = make(map[string]string, len(*in))
+		for key, val := range *in {
+			(*out)[key] = val
+		}
+	}
+	if in.Tolerations != nil {
+		in, out := &in.Tolerations, &out.Tolerations
+		*out = make([]corev1.Toleration, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
+	if in.Affinity != nil {
+		in, out := &in.Affinity, &out.Affinity
+		*out = new(corev1.Affinity)
+		(*in).DeepCopyInto(*out)
+	}
+	if in.TopologySpreadConstraints != nil {
+		in, out := &in.TopologySpreadConstraints, &out.TopologySpreadConstraints
+		*out = make([]corev1.TopologySpreadConstraint, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
+	in.Resources.DeepCopyInto(&out.Resources)
+	if in.SecurityContext != nil {
+		in, out := &in.SecurityContext, &out.SecurityContext
+		*out = new(corev1.PodSecurityContext)
+		(*in).DeepCopyInto(*out)
+	}
+	if in.ContainerSecurityContext != nil {
+		in, out := &in.ContainerSecurityContext, &out.ContainerSecurityContext
+		*out = new(corev1.SecurityContext)
+		(*in).DeepCopyInto(*out)
+	}
+	if in.ExtraEnv != nil {
+		in, out := &in.ExtraEnv, &out.ExtraEnv
+		*out = make([]corev1.EnvVar, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
+	if in.ExtraEnvFrom != nil {
+		in, out := &in.ExtraEnvFrom, &out.ExtraEnvFrom
+		*out = make([]corev1.EnvFromSource, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
+	if in.ExtraVolumes != nil {
+		in, out := &in.ExtraVolumes, &out.ExtraVolumes
+		*out = make([]corev1.Volume, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
+	if in.ExtraVolumeMounts != nil {
+		in, out := &in.ExtraVolumeMounts, &out.ExtraVolumeMounts
+		*out = make([]corev1.VolumeMount, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
+	if in.ImagePullSecrets != nil {
+		in, out := &in.ImagePullSecrets, &out.ImagePullSecrets
+		*out = make([]corev1.LocalObjectReference, len(*in))
+		copy(*out, *in)
+	}
+	if in.DisruptionBudget != nil {
+		in, out := &in.DisruptionBudget, &out.DisruptionBudget
+		*out = new(PodDisruptionBudgetSpec)
+		(*in).DeepCopyInto(*out)
+	}
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new PodSpec.
+func (in *PodSpec) DeepCopy() *PodSpec {
+	if in == nil {
+		return nil
+	}
+	out := new(PodSpec)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *PostgresClusterRef) DeepCopyInto(out *PostgresClusterRef) {
 	*out = *in
@@ -643,6 +767,7 @@ func (in *TerdutServerSpec) DeepCopyInto(out *TerdutServerSpec) {
 	in.Notify.DeepCopyInto(&out.Notify)
 	in.OIDC.DeepCopyInto(&out.OIDC)
 	in.AllowedTeams.DeepCopyInto(&out.AllowedTeams)
+	in.Pod.DeepCopyInto(&out.Pod)
 }
 
 // DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new TerdutServerSpec.