ux and editing plugins configured

lua/plugins/undotree.lua

@@ -0,0 +1,15 @@
+-- Phase 6.8: undotree for visual undo history
+return {
+  'mbbill/undotree',
+  cmd = 'UndotreeToggle',  -- Lazy load on command
+  keys = {
+    { '<leader>u', '<cmd>UndotreeToggle<cr>', desc = 'Toggle Undotree' },
+  },
+  config = function()
+    -- Configure undotree
+    vim.g.undotree_WindowLayout = 2         -- Layout: diff at bottom
+    vim.g.undotree_ShortIndicators = 1      -- Use short time indicators
+    vim.g.undotree_SetFocusWhenToggle = 1   -- Focus undotree when toggled
+    vim.g.undotree_DiffAutoOpen = 1         -- Auto open diff window
+  end,
+}