Merge existing wikis and smartclide-docs

[reimer-atb]

There are currently two repositories that have wiki content:

• smartclide
• smartclide-docs

It should be investigated if the wikis are still needed or if it makes sense to integrate them into the smartclide documentation, which is published at https://eclipse-opensmartclide.github.io/smartclide-docs/.

If a wiki is to be kept, the two existing wikis should be merged to avoid confusion and to have a single source of "truth".

To be coordinated with @phkrief - see also https://gitlab.eclipse.org/eclipsefdn/helpdesk/-/issues/2151