Add Hexology Gwydd65

[Aeonstrife]

Description

Adds support for the Hexology Gwydd65, a 65% RP2040-based keyboard using the Hexology Gwydd65 Solder or Hotswap PCB.

This includes:

• keyboard.json data-driven keyboard definition
• default keymap
• 65% ANSI blocker community layout support
• RGB underglow support
• Caps Lock LED indicator support
• Keyboard readme with build, flash, and bootloader instructions

Hardware:

• Keyboard: Hexology Gwydd65
• PCB: Hexology Gwydd65 Solder PCB, Hexology Gwydd65 Hotswap PCB
• MCU: RP2040
• Availability: https://www.hexology.design/products/gwydd65-keyboard-kit

Validated with:

• qmk lint -kb hexology/gwydd65
• make hexology/gwydd65:all

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

• None

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).