Revise Pod concept (#22603)

* Revise Pod concept

Adapt the existing Pod documentation to suit the Docsy theme, by
promoting the Pod concept itself to /docs/concepts/workloads/pods/

Following on from this, update the Pod Lifecycle page to cover the
lifecycle of a Pod and follow on directly from the Pod concept,
for readers keen to understand things in detail.

This change also removes the automatic contents list from the Pod
overview page. Instead, the new page links to all the pages
inside the Pod section.

* Update links to Pod concept

Link to updated content

* Incorporate Pod concept suggestions

Co-authored-by: Celeste Horgan <celeste@cncf.io>

* Revise StatefulSet suggestion for Pod concept

Co-authored-by: Celeste Horgan <celeste@cncf.io>

Co-authored-by: Celeste Horgan <celeste@cncf.io>

content/en/docs/concepts/cluster-administration/networking.md

@@ -12,7 +12,7 @@ understand exactly how it is expected to work.  There are 4 distinct networking
 problems to address:
 
 1. Highly-coupled container-to-container communications: this is solved by
-   [pods](/docs/concepts/workloads/pods/pod/) and `localhost` communications.
+   {{< glossary_tooltip text="Pods" term_id="pod" >}} and `localhost` communications.
 2. Pod-to-Pod communications: this is the primary focus of this document.
 3. Pod-to-Service communications: this is covered by [services](/docs/concepts/services-networking/service/).
 4. External-to-Service communications: this is covered by [services](/docs/concepts/services-networking/service/).

content/en/docs/concepts/configuration/pod-priority-preemption.md

@@ -255,7 +255,7 @@ makes Pod P eligible to preempt Pods on another Node.
 #### Graceful termination of preemption victims
 
 When Pods are preempted, the victims get their
-[graceful termination period](/docs/concepts/workloads/pods/pod/#termination-of-pods).
+[graceful termination period](/docs/concepts/workloads/pods/pod-lifecycle/#pod-termination).
 They have that much time to finish their work and exit. If they don't, they are
 killed. This graceful termination period creates a time gap between the point
 that the scheduler preempts Pods and the time when the pending Pod (P) can be
@@ -268,7 +268,7 @@ priority Pods to zero or a small number.
 
 #### PodDisruptionBudget is supported, but not guaranteed
 
-A [Pod Disruption Budget (PDB)](/docs/concepts/workloads/pods/disruptions/)
+A [PodDisruptionBudget](/docs/concepts/workloads/pods/disruptions/) (PDB)
 allows application owners to limit the number of Pods of a replicated application
 that are down simultaneously from voluntary disruptions. Kubernetes supports
 PDB when preempting Pods, but respecting PDB is best effort. The scheduler tries

content/en/docs/concepts/containers/container-lifecycle-hooks.md

@@ -42,7 +42,7 @@ so it must complete before the call to delete the container can be sent.
 No parameters are passed to the handler.
 
 A more detailed description of the termination behavior can be found in
-[Termination of Pods](/docs/concepts/workloads/pods/pod/#termination-of-pods).
+[Termination of Pods](/docs/concepts/workloads/pods/pod-lifecycle/#pod-termination).
 
 ### Hook handler implementations
 

content/en/docs/concepts/overview/working-with-objects/kubernetes-objects.md

@@ -92,7 +92,7 @@ and the `spec` format for a Deployment can be found in
 ## {{% heading "whatsnext" %}}
 
 * [Kubernetes API overview](/docs/reference/using-api/api-overview/) explains some more API concepts
-* Learn about the most important basic Kubernetes objects, such as [Pod](/docs/concepts/workloads/pods/pod-overview/).
+* Learn about the most important basic Kubernetes objects, such as [Pod](/docs/concepts/workloads/pods/).
 * Learn about [controllers](/docs/concepts/architecture/controller/) in Kubernetes
 
 

content/en/docs/concepts/workloads/controllers/daemonset.md

@@ -60,7 +60,7 @@ A DaemonSet also needs a [`.spec`](https://git.k8s.io/community/contributors/dev
 
 The `.spec.template` is one of the required fields in `.spec`.
 
-The `.spec.template` is a [pod template](/docs/concepts/workloads/pods/pod-overview/#pod-templates). It has exactly the same schema as a [Pod](/docs/concepts/workloads/pods/pod/), except it is nested and does not have an `apiVersion` or `kind`.
+The `.spec.template` is a [pod template](/docs/concepts/workloads/pods/#pod-templates). It has exactly the same schema as a {{< glossary_tooltip text="Pod" term_id="pod" >}}, except it is nested and does not have an `apiVersion` or `kind`.
 
 In addition to required fields for a Pod, a Pod template in a DaemonSet has to specify appropriate
 labels (see [pod selector](#pod-selector)).

content/en/docs/concepts/workloads/controllers/deployment.md

@@ -13,8 +13,8 @@ weight: 30
 
 <!-- overview -->
 
-A _Deployment_ provides declarative updates for [Pods](/docs/concepts/workloads/pods/pod/) and
-[ReplicaSets](/docs/concepts/workloads/controllers/replicaset/).
+A _Deployment_ provides declarative updates for {{< glossary_tooltip text="Pods" term_id="pod" >}}
+{{< glossary_tooltip term_id="replica-set" text="ReplicaSets" >}}.
 
 You describe a _desired state_ in a Deployment, and the Deployment {{< glossary_tooltip term_id="controller" >}} changes the actual state to the desired state at a controlled rate. You can define Deployments to create new ReplicaSets, or to remove existing Deployments and adopt all their resources with new Deployments.
 
@@ -23,8 +23,6 @@ Do not manage ReplicaSets owned by a Deployment. Consider opening an issue in th
 {{< /note >}}
 
 
-
-
 <!-- body -->
 
 ## Use Case
@@ -1053,8 +1051,7 @@ A Deployment also needs a [`.spec` section](https://git.k8s.io/community/contrib
 
 The `.spec.template` and `.spec.selector` are the only required field of the `.spec`.
 
-The `.spec.template` is a [Pod template](/docs/concepts/workloads/pods/pod-overview/#pod-templates). It has exactly the same schema as a [Pod](/docs/concepts/workloads/pods/pod/), except it is nested and does not have an
-`apiVersion` or `kind`.
+The `.spec.template` is a [Pod template](/docs/concepts/workloads/pods/#pod-templates). It has exactly the same schema as a {{< glossary_tooltip text="Pod" term_id="pod" >}}, except it is nested and does not have an `apiVersion` or `kind`.
 
 In addition to required fields for a Pod, a Pod template in a Deployment must specify appropriate
 labels and an appropriate restart policy. For labels, make sure not to overlap with other controllers. See [selector](#selector)).

content/en/docs/concepts/workloads/controllers/job.md

@@ -122,7 +122,7 @@ A Job also needs a [`.spec` section](https://git.k8s.io/community/contributors/d
 
 The `.spec.template` is the only required field of the `.spec`.
 
-The `.spec.template` is a [pod template](/docs/concepts/workloads/pods/pod-overview/#pod-templates). It has exactly the same schema as a [pod](/docs/user-guide/pods), except it is nested and does not have an `apiVersion` or `kind`.
+The `.spec.template` is a [pod template](/docs/concepts/workloads/pods/#pod-templates). It has exactly the same schema as a {{< glossary_tooltip text="Pod" term_id="pod" >}}, except it is nested and does not have an `apiVersion` or `kind`.
 
 In addition to required fields for a Pod, a pod template in a Job must specify appropriate
 labels (see [pod selector](#pod-selector)) and an appropriate restart policy.

content/en/docs/concepts/workloads/controllers/replicationcontroller.md

@@ -126,7 +126,7 @@ A ReplicationController also needs a [`.spec` section](https://git.k8s.io/commun
 
 The `.spec.template` is the only required field of the `.spec`.
 
-The `.spec.template` is a [pod template](/docs/concepts/workloads/pods/pod-overview/#pod-templates). It has exactly the same schema as a [pod](/docs/concepts/workloads/pods/pod/), except it is nested and does not have an `apiVersion` or `kind`.
+The `.spec.template` is a [pod template](/docs/concepts/workloads/pods/#pod-templates). It has exactly the same schema as a {{< glossary_tooltip text="Pod" term_id="pod" >}}, except it is nested and does not have an `apiVersion` or `kind`.
 
 In addition to required fields for a Pod, a pod template in a ReplicationController must specify appropriate
 labels and an appropriate restart policy. For labels, make sure not to overlap with other controllers. See [pod selector](#pod-selector).