Show description of each group of mods on mod selection screen

Currently, you need to click into each mod to see what the mod is for / whether the mod is no longer recommended or there are alternative options / requirements for the mod.

It would be good if we could group the mods together and describe them right on the index page, so the user doesn't need to click into every mod for information.

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Higurashi Description Text (explain about console here or have own section for console?)

Higurashi Buttons

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Umineko Q/A Description Text

Umineko Q/A Buttons

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Umineko Legacy Description Text

Umineko Legacy Buttons
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- [x] Separate mods into groups (not sure if all umineko should be grouped as one, or as above)
- [ ] Add a description before each group of mods explaining what they are
- [ ] Decide how to handle Higurashi Console arcs
- [x] Remove description on individual umineko pages about alternative patch options

Look at the mod selection screen UI code to understand how mods are currently listed and grouped. Identify where to add descriptive text sections before each mod group. Check existing mod data structures to see if groups are already defined or need to be created. Test changes by running the patcher and verifying descriptions appear correctly without breaking the layout.

Written by the indexing model from the issue text.