Introduce `.msix` installer instead of WiX v3 .msi

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## Feature request

**Is your feature request related to a problem? Please describe.**
- We use **WiX v3** for `.msi` installer, which is **End-Of-Life**
- Some new Windows 11 features are not supported

**Describe the solution you'd like**
1. Check limitations of MSIX
- https://learn.microsoft.com/en-us/windows/msix/desktop/desktop-to-uwp-prepare
2. Add `.msix` installer as the new universal and recommended installer
- Supports modern Windows features
- Supports publishing to Microsoft Store
3. Deprecate the **WiX** `.msi` installer in favour of `.msix`
4. In about a year:
- If everything goes well — support only MSIX
- If the classic `.msi` is still needed — migrate to **WiX v5**

**Describe alternatives you've considered**
It is possible to pack `.msi` inside `.msix`

**Additional context**
- https://github.com/nextcloud/talk-desktop/issues/1519