feat(v1.1.0): major refactor with modular architecture and plugin support

- Add config.lua for comprehensive configuration options
  (transparent, italic_comments, bold_keywords, bold_functions, bold_types, terminal_colors)
- Add highlights.lua with 500+ highlight groups for 30+ plugins
  (Telescope, NvimTree, Neo-tree, GitSigns, nvim-cmp, Lazy.nvim, Mason, etc.)
- Add colors/ directory for :colorscheme command support
- Add terminal colors (16-color palette for :terminal)
- Add test suite (test/test_colors.lua)
- Add development tools (selene.toml, stylua.toml, vim.toml)
- Add CHANGELOG.md following Keep a Changelog format

- Fix colors.lua not being used by init.lua
- Fix setup(opts) not applying configuration options
- Fix README referencing non-existent files

- Update documentation with accurate file structure and API docs

CONTRIBUTING.md

@@ -66,7 +66,15 @@ Thank you for your interest in contributing to CargDev-Cyberpunk.nvim! This docu
 lua/cargdev-cyberpunk/
 ├── init.lua          # Main plugin entry point
 ├── colors.lua        # Color palette definitions
-└── plugin.lua        # Plugin configuration
+├── config.lua        # Configuration management
+├── highlights.lua    # Highlight group definitions
+└── plugin.lua        # Plugin metadata
+
+colors/
+└── cargdev-cyberpunk.lua  # Colorscheme command file
+
+test/
+└── test_colors.lua   # Test suite
 ```
 
 ### Color Guidelines