docs(meshcentral): helmify docs (#32756)

**Description**
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helmify docs
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⚒️ Fixes  # <!--(issue)-->

**⚙️ 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
- [x] 📜 Documentation Changes

**🧪 How Has This Been Tested?**
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**✔️ 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 changes to the documentation
- [ ] 🧪 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
- [x] I made sure the title starts with `feat(chart-name):`,
`fix(chart-name):`, `chore(chart-name):`, `docs(chart-name):` or
`fix(docs):`

**➕ 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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charts/stable/meshcentral/docs/installation-instructions.md

@@ -8,88 +8,13 @@ Ingress for this chart is **required**
 
 :::
 
-In both Native Helm and TrueNAS Scale, keys that start with `_` are **unset**.
+## Unset Keys
 
-## Configuration
-
-### TrueNAS Scale
-
-In order to be able to expose some options in the GUI,
-but also give users the option to users to **unset** those values,
-instead of using our defaults. We decided to do the following.
-
-We will **unset** every option (key) that has:
-
-- Stings: Empty (`"`) value.
-- Arrays: Empty (`[]`) arrays.
-- Int: Value of `-99`.
-  (That's because both `0` and `-1` is valid values on some options
-  and empty int are not possible (at least now) in TrueNAS Scale GUI)
-
-The above will only be applied when installed in TrueNAS Scale as an App
-
-:::note
-
-When you make a change in the UI, you need to manually stop and re-start the app
-for the change to take effect.
-
-:::
-
-For SCALE users, you can add additional configuration options that are not exposed in the UI
-by using the `Additional MeshCentral Configuration` section.
-
-:::tip
-
-However, if you think an option would be used by a lot of users, it would be best to ask us to expose it.
-
-:::
-
-For example to set this:
-
-```json
-"settings": {
-  "sms": {
-    "provider": "twillio"
-  }
-}
-```
-
-Set like this:
-
-- Key: `settigns.sms.provider`
-- Value: `twillio`
-
-For lists:
-
-```json
-"domains": {
-  "": {
-    "newAccoutnsRights": [
-      "item1",
-      "item2"
-    ]
-  }
-}
-```
-
-Set like this:
-
-- Key: `domains."".newAccountsRights`
-- Value: `[ "item1", "item2" ]`
-
-:::caution
-
-Please use the exact casing as in the [MeshCentral's json schema](https://github.com/Ylianst/MeshCentral/blob/master/meshcentral-config-schema.json).
-
-:::
-
-### Native Helm
-
-Native Helm users won't be affected with the above.
+Keys that start with `_` are **unset**.
 
 ## Hardcoded values
 
-We hardcoded some values, so the chart/app can work correctly based on how it's written.
+We hardcoded some values, so the chart can work correctly based on how it's written.
 Those values are:
 
 ```json