How to create Side By Side formulae/cask sharing the same root folder (probably require code/script for uninstall)

[tebeco]

Output of brew config

none yet

Output of brew doctor

none yet

Description of issue

I'm considering adding cask for dotnet and dotnet-sdk, I know there's one already existing but currently the issue is that brew does not allow SxS.
Many linux distro and also winget allow side by side simply by publishing version package per "channel"
so currently instead of having a single cask named dotnet-sdk it would be:

• dotnet-sdk-6 : LTS - Support until 10/11/2026
• dotnet-sdk-7 : STS - Support until 14/05/2024
• dotnet-sdk-8 : LTS - Support until 12/11/2024

The current cask for dotnet-sdk seems "ok" to mimic, the only question I have is about "unpublish" and "uninstall":

• Once the EOL is reached, what's the brew point of view of these cask ? as I see it they probably should be removed since they will stop receiving security update and it should be brew job to deal with "unsafe installer" as the original vendor (MSFT in such case) officially stopped shipping it.
• assuming it needs to be unpublish/removed => brew install/update --cask dotnet-sdk-6 should fail, what's the way of doing that ? simply remove the .go / .rb from the repo here ?
• what's the way to properly uninstall specific file from specific folder with brew ? reason for that question is that dotnet uses the same root folder and install specific sub-folder for versioning

The current official way to uninstall look like it should be scripted because it look like this:
(generally the recommendation is to keep only the latest per channel, and uninstall every other)