Project rename to `ironcore`

[Andreas Fritzler]

Summary

Renaming tasks after project move:

• Ensure all build artefacts are prefixed with ironcore
• Ensure that all deployment yamls have the ironcore naming scheme
• Ensure that github.com/ironcore-dev/controller-utils is used and all imports are changed accordingly
• Ensure that github.com/ironcore-dev/ironcore is used and all imports are changed accordingly
• Ensure that ironcore is used in the Makefile
• Ensure that ironcore is used in all docs and README files