[refactor] Cleanup code

- Rename joystick library to helpers
- Put color565 function in helpers.py
- Switch screen width and height names as game runs in landscrape
- Enumerate levels for readability
- Update docstrings
- Rework splash screen to use binary operators
- Extract create bricks and create lives functions
- Reowrk main game loop logic to support next level

helpers.py

@@ -0,0 +1,23 @@
+from machine import Pin
+
+# Joystick class to handle joystick input
+class Joystick:
+    def __init__(self):
+        # Map buttons
+        self.button_a = Pin(15, Pin.IN, Pin.PULL_UP)
+        self.button_b = Pin(17, Pin.IN, Pin.PULL_UP)
+        # Map joystick
+        self.joy_up = Pin(2, Pin.IN, Pin.PULL_UP)
+        self.joy_down = Pin(18, Pin.IN, Pin.PULL_UP)
+        self.joy_left = Pin(16, Pin.IN, Pin.PULL_UP)
+        self.joy_right = Pin(20, Pin.IN, Pin.PULL_UP)
+        self.joy_click = Pin(3, Pin.IN, Pin.PULL_UP)
+
+
+def color565(red: int, green: int, blue: int) -> int:
+    """Convert RGB888 to RGB565."""
+    return (
+        (((green & 0b00011100) << 3) + ((red & 0b11111000) >> 3) << 8) 
+        + (blue & 0b11111000) 
+        + ((green & 0b11100000) >> 5)
+        )