Move lsp config to local file structure

.config/nvim/lsp/css_variables.lua

@@ -0,0 +1,51 @@
+---@brief
+---
+--- https://github.com/vunguyentuan/vscode-css-variables/tree/master/packages/css-variables-language-server
+---
+--- CSS variables autocompletion and go-to-definition
+---
+--- `css-variables-language-server` can be installed via `npm`:
+---
+--- ```sh
+--- npm i -g css-variables-language-server
+--- ```
+
+---@type vim.lsp.Config
+return {
+  cmd = { 'css-variables-language-server', '--stdio' },
+  filetypes = { 'css', 'scss', 'less' },
+
+  -- Taken from lsp/ts_ls.lua to handle simple projects and monorepos.
+  root_dir = function(bufnr, on_dir)
+    local root_markers = { 'package-lock.json', 'yarn.lock', 'pnpm-lock.yaml', 'bun.lockb', 'bun.lock' }
+    -- Give the root markers equal priority by wrapping them in a table
+    root_markers = vim.fn.has 'nvim-0.11.3' == 1 and { root_markers, { '.git' } }
+      or vim.list_extend(root_markers, { '.git' })
+    -- We fallback to the current working directory if no project root is found
+    local project_root = vim.fs.root(bufnr, root_markers) or vim.fn.getcwd()
+
+    on_dir(project_root)
+  end,
+
+  -- Same as inlined defaults that don't seem to work without hardcoding them in the lua config
+  -- https://github.com/vunguyentuan/vscode-css-variables/blob/763a564df763f17aceb5f3d6070e0b444a2f47ff/packages/css-variables-language-server/src/CSSVariableManager.ts#L31-L50
+  settings = {
+    cssVariables = {
+      lookupFiles = { '**/*.less', '**/*.scss', '**/*.sass', '**/*.css' },
+      blacklistFolders = {
+        '**/.cache',
+        '**/.DS_Store',
+        '**/.git',
+        '**/.hg',
+        '**/.next',
+        '**/.svn',
+        '**/bower_components',
+        '**/CVS',
+        '**/dist',
+        '**/node_modules',
+        '**/tests',
+        '**/tmp',
+      },
+    },
+  },
+}