Added a start screen, loadout scene, and ending scene.

Added a start screen, loadout scene, and ending scene.

Also added triggers to objects, the ability to focus on enemies, and X-key special attacks for weapons 1, 2, and 3.

① Added start screen

② Added loadout scene

③ UI changes

④ Made weapons 1, 2, and 3 usable with the X key

⑤ Reduced enemy explosion and bullet penetration indoors

⑥ Lighting changes

⑦ Added object triggers when focusing on them

⑧ Added ending scene after Story 4-2