only use the node cmd if it exists

lua/plugins/copilot.lua

@@ -3,6 +3,11 @@ return {
   cmd = 'Copilot',
   event = 'InsertEnter',
   config = function()
+    local node_cmd = nil
+    local docker_node = vim.fn.expand('$HOME') .. '/.nvm/versions/node/v22.12.0/bin/node'
+    if vim.fn.executable(docker_node) == 1 then
+      node_cmd = docker_node
+    end
     require('copilot').setup({
       filetypes = {
         yaml = false,
@@ -17,7 +22,7 @@ return {
         cpp = true,
         ['.'] = false,
       },
-      copilot_node_command = vim.fn.expand('$HOME') .. '/.nvm/versions/node/v22.12.0/bin/node',
+      copilot_node_command = node_cmd,
       suggestion = { enabled = false, auto_trigger = false },
       panel = { enabled = false },
     })