Optimize Neovim configuration structure and LSP setup

- Remove duplicate nvim-web-devicons loading (already in kickstart)
- Add clangd configuration to custom LSP setup with proper flags
- Replace complex clangd_helper with universal LSP reload keybind (<leader>lr)
- Clean up unused clangd target selection keybind
- Streamline plugin organization for better maintainability

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

lua/custom/plugins/init.lua

@@ -3,14 +3,6 @@
 --
 -- See the kickstart.nvim README for more information
 return {
-  {
-    'nvim-tree/nvim-web-devicons',
-    lazy = false,
-    priority = 1000,
-    config = function()
-      require('nvim-web-devicons').setup()
-    end,
-  },
   -- { import = 'custom.plugins.completion' },
   -- { import = 'custom.plugins.debug' },
   -- { import = 'custom.plugins.formatting' },