Fix RibbonVerifier4 not checking gen4 contest ribbons correctly
Split IRibbonCommon6 to have memory ribbons separate, as they are not implemented in mystery gifts. Also, we can add the boolean flags to the interface, and check that the boolean is set if count is nonzero.
Fix adding ribbons to Gen8 gift templates
Improve Gen8 template ribbon fetch (no closure, faster IndexOf)
* Rewrite ribbon verification
* Explicitly verifies all ribbons instead of chained iterators.
* Verifies using only the stack, using `struct` and `Span<T>`. No allocation on heap, or `IEnumerable` iterators.
* Verifies all egg ribbons using a separate method, explicitly implemented. No reflection overhead.
* Separates each ribbon interface to separate `static` classes. Easier to identify code needing change on new game update.
* Extracted logic for specific ribbons. Can easily revise complicated ribbon's acquisition rules.
* Simplifies GiveAll/RemoveAll legal ribbon mutations. No reflection overhead, and no allocation.
* Can be expanded in the future if we need to track conditions for ribbon acquisition (was Sinnoh Champ received in BDSP or Gen4?)
End result is a more performant implementation and easier to maintain & reuse logic.