Add new keyboard: Cue2Keys

[esplo]

Adds support for the Cue2Keys keyboard.

Description

The Cue2Keys keyboard is modular, allowing users to connect modules such as keys, trackballs, and rotary encoders to configure the keyboard. The number and types of connected modules are detected during startup. Key presses and rotary encoder clicks are mapped to the key matrix in the order of their I2C addresses.

The trackball module is directly connected to the microcontroller pins, while other modules are connected via I2C. Since multiple trackballs can be connected with some additional features, the existing ADNS-5050 driver code has been modified, and a custom driver has been created under the driver folder.

Types of Changes

• Core
• Bugfix
• New feature
• Enhancement/optimization
• Keyboard (addition or update)
• Keymap/layout (addition or update)
• Documentation

Issues Fixed or Closed by This PR

• N/A

Checklist

• My code follows the code style of this project: C, Python
• I have read the PR Checklist document and have made the appropriate changes.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• I have tested the changes and verified that they work and don't break anything (as well as I can manage).