* Add Windows MSI installer with WiX v6
Build a dual-scope MSI installer that lets users choose per-user
(%LocalAppData%\Zellij) or per-machine (Program Files\Zellij) install,
with automatic PATH configuration and clean uninstall support.
- Custom UI based on stock WixToolset.UI.wixext dialogs to work around
the long-standing WixUI_Advanced dual-scope bug (wixtoolset/issues#7137)
- Custom folder resolution CAs (SetFolderPerUser/SetFolderPerMachine)
- Embed application icon into zellij.exe via embed-resource
- Icon shown in Add/Remove Programs via ARPPRODUCTICON
- MSI build integrated into release.yml CI workflow
* Add MSI installer to no-web build and fix artifact naming
- Add MSI build steps to build-release-noweb job
- Add SHA256 checksums for MSI artifacts
- Pin WixToolset.UI.wixext to 6.0.2 to avoid v7 RC incompatibility
- Use -installer suffix after target in artifact names
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Co-authored-by: divens <divens.dev@gmail.com>
