engine: add inline examples for managing labels on Docker objects

Addresses #7462 — the labels page only linked to the Dockerfile LABEL
instruction for adding labels to images. Rewrote the section with
inline examples showing how to add, inspect, and filter labels for
each object type, including the docker build --label flag.

Author: dvdksn

content/manuals/engine/manage-resources/labels.md

@@ -70,47 +70,122 @@ you build this functionality into third-party tooling.
 ## Manage labels on objects
 
 Each type of object with support for labels has mechanisms for adding and
-managing them and using them as they relate to that type of object. These links
-provide a good place to start learning about how you can use labels in your
-Docker deployments.
+managing them and using them as they relate to that type of object.
 
-Labels on images, containers, local daemons, volumes, and networks are static for
-the lifetime of the object. To change these labels you must recreate the object.
-Labels on Swarm nodes and services can be updated dynamically.
+Labels on images, containers, local daemons, volumes, and networks are static
+for the lifetime of the object. To change these labels you must recreate the
+object. Labels on Swarm nodes and services can be updated dynamically.
 
-- Images and containers
+### Images
 
-  - [Adding labels to images](/reference/dockerfile.md#label)
-  - [Overriding a container's labels at runtime](/reference/cli/docker/container/run/#label)
-  - [Inspecting labels on images or containers](/reference/cli/docker/inspect/)
-  - [Filtering images by label](/reference/cli/docker/image/ls/#filter)
-  - [Filtering containers by label](/reference/cli/docker/container/ls/#filter)
+Add labels to images using the [`LABEL` instruction](/reference/dockerfile.md#label) in a Dockerfile:
 
-- Local Docker daemons
+```dockerfile
+LABEL com.example.version="1.0"
+LABEL com.example.description="Web application"
+```
 
-  - [Adding labels to a Docker daemon at runtime](/reference/cli/dockerd.md)
-  - [Inspecting a Docker daemon's labels](/reference/cli/docker/system/info/)
+You can also set labels at build time with the `--label` flag, without needing
+a `LABEL` instruction in the Dockerfile:
 
-- Volumes
+```console
+$ docker build --label "com.example.version=1.0" -t myapp .
+```
 
-  - [Adding labels to volumes](/reference/cli/docker/volume/create/)
-  - [Inspecting a volume's labels](/reference/cli/docker/volume/inspect/)
-  - [Filtering volumes by label](/reference/cli/docker/volume/ls/#filter)
+Inspect labels on an image using `docker inspect`:
 
-- Networks
+```console
+$ docker inspect --format='{{json .Config.Labels}}' myapp
+```
 
-  - [Adding labels to a network](/reference/cli/docker/network/create/)
-  - [Inspecting a network's labels](/reference/cli/docker/network/inspect/)
-  - [Filtering networks by label](/reference/cli/docker/network/ls/#filter)
+Filter images by label with [`docker image ls --filter`](/reference/cli/docker/image/ls/#filter):
 
-- Swarm nodes
+```console
+$ docker image ls --filter "label=com.example.version"
+```
 
-  - [Adding or updating a Swarm node's labels](/reference/cli/docker/node/update/#label-add)
-  - [Inspecting a Swarm node's labels](/reference/cli/docker/node/inspect/)
-  - [Filtering Swarm nodes by label](/reference/cli/docker/node/ls/#filter)
+### Containers
 
-- Swarm services
-  - [Adding labels when creating a Swarm service](/reference/cli/docker/service/create/#label)
-  - [Updating a Swarm service's labels](/reference/cli/docker/service/update/)
-  - [Inspecting a Swarm service's labels](/reference/cli/docker/service/inspect/)
-  - [Filtering Swarm services by label](/reference/cli/docker/service/ls/#filter)
+Override or add labels when starting a container with
+[`docker run --label`](/reference/cli/docker/container/run/#label):
+
+```console
+$ docker run --label "com.example.env=prod" myapp
+```
+
+Inspect labels on a container:
+
+```console
+$ docker inspect --format='{{json .Config.Labels}}' mycontainer
+```
+
+Filter containers by label with [`docker container ls --filter`](/reference/cli/docker/container/ls/#filter):
+
+```console
+$ docker container ls --filter "label=com.example.env=prod"
+```
+
+### Local Docker daemons
+
+Add labels to the Docker daemon by passing `--label` flags when starting
+`dockerd`, or by setting `"labels"` in the
+[daemon configuration file](/reference/cli/dockerd.md#daemon-configuration-file):
+
+```json
+{
+  "labels": ["com.example.environment=production"]
+}
+```
+
+View daemon labels with `docker system info`.
+
+### Volumes
+
+Add labels when [creating a volume](/reference/cli/docker/volume/create/):
+
+```console
+$ docker volume create --label "com.example.purpose=database" myvolume
+```
+
+Inspect volume labels:
+
+```console
+$ docker volume inspect myvolume --format='{{json .Labels}}'
+```
+
+Filter volumes by label with [`docker volume ls --filter`](/reference/cli/docker/volume/ls/#filter):
+
+```console
+$ docker volume ls --filter "label=com.example.purpose"
+```
+
+### Networks
+
+Add labels when [creating a network](/reference/cli/docker/network/create/):
+
+```console
+$ docker network create --label "com.example.purpose=frontend" mynetwork
+```
+
+Inspect network labels:
+
+```console
+$ docker network inspect mynetwork --format='{{json .Labels}}'
+```
+
+Filter networks by label with [`docker network ls --filter`](/reference/cli/docker/network/ls/#filter):
+
+```console
+$ docker network ls --filter "label=com.example.purpose"
+```
+
+### Swarm nodes
+
+- [Adding or updating a Swarm node's labels](/reference/cli/docker/node/update/#label-add)
+- [Filtering Swarm nodes by label](/reference/cli/docker/node/ls/#filter)
+
+### Swarm services
+
+- [Adding labels when creating a Swarm service](/reference/cli/docker/service/create/#label)
+- [Updating a Swarm service's labels](/reference/cli/docker/service/update/)
+- [Filtering Swarm services by label](/reference/cli/docker/service/ls/#filter)