Enhance localization and world generation features

- Added new UI strings for menus, settings, and pause functionality in both English and Russian localization files.
- Introduced a new WorldPresetDef class to define world size and population settings, allowing for dynamic world creation.
- Updated world generation logic to support customizable terrain smoothing and population settings based on user-defined presets.
- Refactored WorldScene to utilize the new WorldConfig structure for improved world initialization and loading.

This commit improves the user experience by providing more options for world creation and enhancing the overall localization of the game.

Mods/Core/Languages/en/ui.json

@@ -2,6 +2,59 @@
   "hud.world": "LittleSim | seed {0} | population {1} | {2} FPS",
   "hud.terrain": "LittleSim | terrain | seed {0} | animals: {1}",
   "hud.controls": "WASD — camera, wheel — zoom, ` — console ('help' lists commands)",
+  "hud.paused": "PAUSED",
+
+  "menu.title": "LittleSim",
+  "menu.subtitle": "a god-game: minimal graphics, deep simulation",
+  "menu.newworld": "New World",
+  "menu.load": "Load",
+  "menu.settings": "Settings",
+  "menu.credits": "Credits",
+  "menu.quit": "Quit",
+
+  "newworld.title": "New World",
+  "newworld.name": "Name",
+  "newworld.defaultname": "New World",
+  "newworld.size": "Size",
+  "newworld.seed": "Seed",
+  "newworld.random": "Random",
+  "newworld.smoothing": "Terrain smoothing",
+  "newworld.create": "Create",
+  "newworld.back": "Back",
+
+  "load.title": "Load",
+  "load.empty": "No saves yet",
+  "load.load": "Load",
+  "load.delete": "Delete",
+  "load.back": "Back",
+
+  "settings.title": "Settings",
+  "settings.language": "Language",
+  "settings.fullscreen": "Fullscreen",
+  "settings.vsync": "Vertical sync",
+  "settings.resolution": "Resolution",
+  "settings.volume": "Volume",
+  "settings.apply": "Apply",
+  "settings.back": "Back",
+
+  "pause.title": "Paused",
+  "pause.resume": "Resume",
+  "pause.settings": "Settings",
+  "pause.save": "Save",
+  "pause.mainmenu": "Main menu",
+  "pause.quit": "Quit",
+  "pause.saved": "Saved: {0}",
+
+  "speed.pause": "⏸",
+
+  "credits.title": "Credits",
+  "credits.author": "mrleo1nid",
+  "credits.role": "Concept, code, mrgameeng engine",
+  "credits.back": "Back",
+
+  "preset.small": "Small",
+  "preset.medium": "Medium",
+  "preset.large": "Large",
 
   "terrain.deepwater": "deep water",
   "terrain.water": "water",