Unimplented mons should not show normally in dex

Summary

(Please summarize your feature request concisely) it feels strange for pokemon that arent implemented currently to appear in the dex, the default state should have them hidden possible controls being

• just a config options, on off simple
• only appearing if the mon is registered via command or a datapack that doesnt properly set the implemented flag
• only appearing in creative mode

these options are not mutually exclusive

What are the projected benefits of this feature?

• cleaner and concise dex experience
• no more having so many red xs in the list

What could speak against this feature?

• could be difficult to implement properly
• may cause mons to not show even when registered

Why do you think the benefits outweigh the cons?

(Explain why you think the benefits outweigh the cons) it would provide a more polished look to cobblemon to not show those entries all the time

Mods involved besides Cobblemon

(Does your suggestion require any other mods besides Cobblemon? If so, please list them here)

Sketches, screenshots and/or videos

(Feel free to add any sketches, screenshots or videos that might help the Design team understand your suggestion)

Additional Information

(Is there anything else you would like to add?)