Add documentation for clustertool talos kubeconfig command (#32159)

**Description**
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Please include a summary of the change and which issue is fixed. Please
also include relevant motivation and context. List any dependencies that
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Added the documentation to the `clustertool talos kubeconfig`, I needed
to use this command and I saw it in the help page `clustertool talos -h`
and source code, but not in the documentation online that I was using as
reference. I tried to add the required page
⚒️ Fixes  # <!--(issue)-->
No fixes made
**⚙️ Type of change**

- [ ] ⚙️ Feature/App addition
- [ ] 🪛 Bugfix
- [ ] ⚠️ Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] 🔃 Refactor of current code

**🧪 How Has This Been Tested?**
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Please describe the tests that you ran to verify your changes. Provide
instructions so we can reproduce. Please also list any relevant details
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I checked the help page of the command `clustertool talos kubeconfig`

**📃 Notes:**
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I never programmed in Go, but i wanted to check in the source code to be
sure to not write a bad documentation. It seems to me that this command
is just a wrapper around the `talosctl kubeconfig -n <NodeIP>`, but it
seams to use a function called `gencmd.GenPlain(...)` that seems to wrap
the talosctl command verbatim. If it does it the help page should be
different and also the section related to the option in my
documentation.

![250216-152545_screenshot-area](https://github.com/user-attachments/assets/9a768f3e-4219-4953-8c90-91f2993be385)

![250216-152442_screenshot-area](https://github.com/user-attachments/assets/5d3e4557-4585-4219-9d0d-31b54fec3acb)

**✔️ Checklist:**

- [ ] ⚖️ My code follows the style guidelines of this project
- [ ] 👀 I have performed a self-review of my own code
- [ ] #️⃣ I have commented my code, particularly in hard-to-understand
areas
- [x] 📄 I have made corresponding changes to the documentation
- [ ] ⚠️ My changes generate no new warnings
- [ ] 🧪 I have added tests to this description that prove my fix is
effective or that my feature works
- [ ] ⬆️ I increased versions for any altered app according to semantic
versioning
- [ ] I made sure the title starts with `feat(chart-name):`,
`fix(chart-name):` or `chore(chart-name):`

**➕ App addition**

If this PR is an app addition please make sure you have done the
following.

- [ ] 🖼️ I have added an icon in the Chart's root directory called
`icon.png`

---

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website/src/content/docs/clustertool/commands/talos/kubeconfig.md

@@ -0,0 +1,32 @@
+---
+title: talos kubeconfig
+---
+## clustertool talos kubeconfig
+
+The `kubeconfig` command downloads the admin kubeconfig file from the Talos node in order to manage the Kubernetes cluster with the `kubectl` command.
+
+### Usage
+
+```
+clustertool talos kubeconfig <NodeIP> [flags]
+```
+
+`<NodeIP>` is an optional argument that specifies the Talos node from which to download the configuration file. You can use `all` to select all nodes. By default, this is set to `all`.
+
+### Examples
+
+```
+clustertool talos kubeconfig all
+```
+
+### Options
+
+```
+  -h, --help   help for talos kubeconfig
+```
+
+### Options inherited from parent commands
+
+```
+  --cluster string   Cluster name (default "main")
+```