docs(kubernetes): suggest the use of an init container to download mods which disallow project distribution

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### Enhancement Type

Improve an existing feature

### Describe the enhancement

Some mods disallow project distribution and have to be download manually. This can be tricky for containerised environments, especially for Kubernetes. It might be nice to document the use of an init container to download these assets automatically. See what I've done as an example [here](https://github.com/uhthomas/automata/blob/b65328f8f51ac8e8e353551749466e3ee2844b72/k8s/unwind/minecraft/cf_atm8/stateful_set_list.cue#L36-L61).

It might also be possible to write something quick for Docker compose too?

```
minecraft-cf-atm8-0 minecraft-server [mc-image-helper] 12:20:47.139 WARN : The authors of the mod 'Fix Experience Bug (now with FABRIC and FORGE versions)' have disallowed project distribution. Manually download the file 'ExperienceBugFix-1.19-1.41.2.3.jar' from https://www.curseforge.com/minecraft/mc-mods/fix-experience-bug and supply the mod file separately.
minecraft-cf-atm8-0 minecraft-server [mc-image-helper] 12:20:45.911 WARN : The authors of the mod 'More Overlays Updated' have disallowed project distribution. Manually download the file '[1.19.2] MoreOverlays 1.21.5' from https://www.curseforge.com/minecraft/mc-mods/more-overlays-updated and supply the mod file separately.
minecraft-cf-atm8-0 minecraft-server [mc-image-helper] 12:20:47.165 WARN : The authors of the mod 'Hexerei' have disallowed project distribution. Manually download the file 'hexerei-0.3.0.jar' from https://www.curseforge.com/minecraft/mc-mods/hexerei and supply the mod file separately.
```

The linked example rendered as yaml:

```yaml
initContainers:
- name: download
image: curlimages/curl:8.1.1
args:
- -C
- '-'
- -LOf
- '{https://mediafilez.forgecdn.net/files/4178/188/ExperienceBugFix-1.19-1.41.2.3.jar,https://mediafilez.forgecdn.net/files/4322/445/moreoverlays-1.21.5-mc1.19.2.jar,https://mediafilez.forgecdn.net/files/4466/686/hexerei-0.3.0.jar}'
workingDir: /downloads
resources:
limits:
cpu: "1"
memory: 1Gi
volumeMounts:
- name: downloads
mountPath: /downloads
imagePullPolicy: IfNotPresent
securityContext:
capabilities:
drop:
- ALL
readOnlyRootFilesystem: true
allowPrivilegeEscalation: false
```

Locate the repository's Kubernetes documentation and any Docker Compose guidance, then compare their existing patterns with the linked stateful_set_list.cue example. Document how users can use an init container to download manually supplied mod assets, and clarify whether a Docker Compose example is in scope; done means the relevant containerized deployment guidance is complete and understandable.

Written by the indexing model from the issue text.