* 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

lua/custom/plugins/bufferline.lua

@@ -0,0 +1,17 @@
+return {
+    {
+        'akinsho/bufferline.nvim',
+        config = function ()
+            require("bufferline").setup {
+                options = {
+                    indicator = { style = "icon", icon = "▎"},
+                    diagnostics = 'nvim_lsp', -- | "nvim_lsp" | "coc",
+                    diagnostics_update_in_insert = false,
+                    offsets = { { filetype = "NvimTree", text = "", padding = 1 } },
+                    separator_style = "thin", -- | "thick" | "thin" | { 'any', 'any' },
+                    always_show_bufferline = true,
+                }
+            }
+        end
+    }
+}