Move lsp config to local file structure

.config/nvim/lsp/ast_grep.lua

@@ -0,0 +1,48 @@
+---@brief
+---
+--- https://ast-grep.github.io/
+---
+--- ast-grep(sg) is a fast and polyglot tool for code structural search, lint, rewriting at large scale.
+--- ast-grep LSP only works in projects that have `sgconfig.y[a]ml` in their root directories.
+--- ```sh
+--- npm install [-g] @ast-grep/cli
+--- ```
+
+---@type vim.lsp.Config
+return {
+  cmd = { 'ast-grep', 'lsp' },
+  workspace_required = true,
+  reuse_client = function(client, config)
+    config.cmd_cwd = config.root_dir
+    return client.config.cmd_cwd == config.cmd_cwd
+  end,
+  filetypes = { -- https://ast-grep.github.io/reference/languages.html
+    'bash',
+    'c',
+    'cpp',
+    'cs',
+    'css',
+    'elixir',
+    'go',
+    'haskell',
+    'html',
+    'java',
+    'javascript',
+    'javascriptreact',
+    'json',
+    'kotlin',
+    'lua',
+    'nix',
+    'php',
+    'python',
+    'ruby',
+    'rust',
+    'scala',
+    'solidity',
+    'swift',
+    'typescript',
+    'typescriptreact',
+    'yaml',
+  },
+  root_markers = { 'sgconfig.yaml', 'sgconfig.yml' },
+}