feat: Add new game screen

- Add first person view screen
- Add HippieCrosshair class
- Controls for crosshair options
- Add styles to game module

source/style/modules/_game.scss

@@ -1,3 +1,5 @@
+@use "sass:map";
+
 @use "../hippie-style/hippie";
 
 .body_game {
@@ -24,4 +26,21 @@
 			}
 		}
 	}
+}
+
+.body_fpv {
+	@extend .h_full_view;
+
+	canvas {
+		display: block;
+		cursor: none;
+		background-color: lightblue;
+	}
+
+	.controls {
+		position: fixed;
+		top: 0;
+		left: 0;
+		border-radius: hippie.$radius_basic;
+	}
 }