Add CLAUDE.md and improve clangd configuration

- Add CLAUDE.md with nvim configuration guidance for future Claude instances
- Rename clangd.lua to clangd_helper.lua for better organization
- Document modular structure, LSP setup, and common commands
- Include information about kickstart.nvim fork and conflict-minimizing design

🤖 Generated with Claude Code (claude.ai/code)

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

CLAUDE.md

@@ -0,0 +1,61 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Neovim Configuration Structure
+
+This is a Neovim configuration forked from https://github.com/nvim-lua/kickstart.nvim and structured to minimize merge conflicts when updating from upstream. All custom modifications are isolated in the `lua/custom/` directory, allowing the main `init.lua` and kickstart files to be updated with minimal conflicts.
+
+The configuration is organized in a modular structure:
+
+- **`init.lua`**: Main configuration file that loads all settings, keymaps, and plugins
+- **`lua/custom/`**: Custom configuration modules
+  - **`options.lua`**: Custom vim options (indentation, Nerd Font settings)
+  - **`keymaps.lua`**: Custom key mappings
+  - **`plugins/`**: Plugin configurations
+    - **`init.lua`**: Plugin imports and basic plugin setup
+    - **`lsp/`**: LSP-specific configurations
+      - **`lsp.lua`**: LSP server configurations (Python, Nix, Rust, Go, C/C++)
+      - **`clangd_helper.lua`**: Advanced clangd setup with compile_commands.json detection and file watching
+
+## LSP Configuration
+
+The LSP setup includes:
+- **clangd**: C/C++ with automatic compile_commands.json detection and file watching
+- **pyright**: Python language server with basic type checking
+- **nixd**: Nix language server  
+- **ruff**: Python linter
+- **texlab**: LaTeX support
+- **cmake**: CMake language server
+
+The clangd configuration in `lua/custom/plugins/lsp/clangd_helper.lua` automatically:
+- Searches for compile_commands.json files using `fd`
+- Watches for changes and restarts clangd when compile_commands.json is updated
+- Provides a `:ReloadClangd` command for manual restart
+
+## Key Features
+
+- Uses **lazy.nvim** for plugin management
+- **Blink.cmp** for autocompletion with LSP integration
+- **Telescope** for fuzzy finding
+- **Treesitter** for syntax highlighting
+- **Which-key** for keymap help
+- **Mini.nvim** modules for text objects, surround, and statusline
+- **TokyoNight** colorscheme
+
+## Common Commands
+
+- `:Lazy` - Manage plugins (install, update, etc.)
+- `:checkhealth` - Check Neovim configuration health
+- `:ReloadClangd` - Manually restart clangd LSP server
+- `<space>sh` - Search help documentation
+- `<space>sf` - Find files
+- `<space>sg` - Live grep search
+- `<space>f` - Format current buffer
+
+## Development Workflow
+
+1. Configuration changes are made in `lua/custom/` files
+2. Plugin configurations go in `lua/custom/plugins/`
+3. LSP servers are expected to be installed system-wide (via Nix/Home Manager based on comments)
+4. The configuration uses lazy loading for most plugins to optimize startup time

lua/custom/plugins/lsp/lsp.lua

@@ -1,6 +1,12 @@
 -- ~/dlond/nvim/lua/custom/plugins/lsp.lua
 -- LSP configuration, assuming LSP servers are installed via Nix/Home Manager
 
+return {
+  {
+    'neovim/nvim-lspconfig',
+    -- only load when editing these filetypes (optional)
+    ft = { 'python', 'lua', 'nix', 'rust', 'go' },
+    opts = function()
       local lspconfig = require 'lspconfig'
       local capabilities = require('blink.cmp').get_lsp_capabilities()
 
@@ -15,8 +21,8 @@ local servers = {
                 typeCheckingMode = 'basic',
               },
             },
-      positionEncoding = 'utf-8',
           },
+          positionEncoding = 'utf-8',
         },
         nixd = {},
         ruff = {},
@@ -26,11 +32,26 @@ local servers = {
           filetypes = { 'cmake' },
           root_dir = require('lspconfig.util').root_pattern('CMakeLists.txt', '.git'),
         },
+        clangd = (function()
+          local cmd = { 'clangd', '--background-index' }
+          return {
+            cmd = cmd,
+            filetypes = { 'c', 'cpp', 'objc', 'objcpp', 'cuda' },
+            root_dir = lspconfig.util.root_pattern('compile_commands.json', '.git'),
+            single_file_support = true,
+            -- on_attach = function(client, bufnr)
+            --   local util = require(custom.plugins.lsp.clangd_helper)
+            --   util.notify_compile_commands(bufnr)
+            --   util.start_compile_commands_watcher(client, bufnr)
+            -- end,
+          }
+        end)(),
       }
 
-for server_name, server in pairs(servers) do
-  server.capabilities = vim.tbl_deep_extend('force', {}, capabilities, server.capabilities or {})
-  lspconfig[server_name].setup(server)
+      for name, config in pairs(servers) do
+        config.capabilities = vim.tbl_deep_extend('force', {}, capabilities, config.capabilities or {})
+        lspconfig[name].setup(config)
       end
-
-return {}
+    end,
+  },
+}