Add Titan map with random spawn nations - along new Cosmic map category (#4183)

Resolves #4182

## Description:

Adds "Titan" (real moon of Saturn with methane seas) map . Uses new
random spawn nation feature by FloPinguin.
https://github.com/openfrontio/OpenFrontIO/pull/4156

Also adds new Cosmic map category. The "Other" map category has become a
wastebasket of unrelated maps, and with increasing number of maps, i
think its a good addition to have better categories for these maps.

I figured these 2 changes should go together since im adding a cosmic
map, and a cosmic category.

proof of nations spawning randomly and how the cosmic category looks in
the menu:


https://github.com/user-attachments/assets/b84bd3ef-6b8f-46fe-a6ea-ea5e79c6dc00

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory

## Please put your Discord username so you can be contacted if a bug or
regression is found:

tri.star1011

---------

Co-authored-by: Evan <evanpelle@gmail.com>

src/server/MapPlaylist.ts

@@ -108,6 +108,7 @@ const FREQUENCY: Partial<Record<GameMapName, number>> = {
   Svalmel: 8,
   TaiwanStrait: 5,
   TheBox: 3,
+  Titan: 3,
   TradersDream: 4,
   TwoLakes: 6,
   Venice: 6,