* feat(nvim-tree.lua): add autocmd to close NvimTree on QuitPre event and open NvimTree on VimEnter event

* feat(bufferline.lua): add configuration for bufferline plugin with options for indicator, diagnostics, offsets, separator_style, and always_show_bufferline

after/plugin/nvim-tree.lua

@@ -0,0 +1,12 @@
+vim.api.nvim_create_autocmd({"QuitPre"}, {
+    callback = function() vim.cmd("NvimTreeClose") end,
+})
+
+
+local function open_nvim_tree()
+
+  -- open the tree
+  require("nvim-tree.api").tree.open()
+end
+
+vim.api.nvim_create_autocmd({ "VimEnter" }, { callback = open_nvim_tree })