refactor(utils): Use vim.validate() form 1 for Neovim 0.11 compatibility (#506)

* refactor(utils): update deprecated Neovim 0.11 APIs

- Replaced vim.validate() with Lua-style type checks
- Future-proofed utility functions for Neovim 0.11+

* refactor(utils): switch to vim.validate() form 1 for Neovim 0.11+

Replaced custom assert() checks with official vim.validate() form 1,
as recommended in Neovim 0.11+ to ensure better consistency with
core APIs and forward compatibility.

* refactor(utils): restore some deleted comments

Author: Chamal1120

lua/dashboard/utils.lua

@@ -26,9 +26,7 @@ function utils.element_align(tbl)
 end
 
 function utils.get_max_len(contents)
-  vim.validate({
-    contents = { contents, 't' },
-  })
+  vim.validate('contents', contents, 'table')
   local cells = {}
   for _, v in pairs(contents) do
     table.insert(cells, vim.api.nvim_strwidth(v))
@@ -39,9 +37,7 @@ end
 
 -- draw the graphics into the screen center
 function utils.center_align(tbl)
-  vim.validate({
-    tbl = { tbl, 'table' },
-  })
+  vim.validate('tbl', tbl, 'table')
   local function fill_sizes(lines)
     local fills = {}
     for _, line in pairs(lines) do
@@ -100,7 +96,7 @@ function utils.disable_move_key(bufnr)
   end, keys)
 end
 
---- return the most recently files list
+-- return the most recently files list
 function utils.get_mru_list()
   local mru = {}
   for _, file in pairs(vim.v.oldfiles or {}) do
@@ -122,9 +118,10 @@ function utils.get_package_manager_stats()
   local status, lazy = pcall(require, 'lazy')
   if status then
     package_manager_stats.name = 'lazy'
-    package_manager_stats.loaded = lazy.stats().loaded
-    package_manager_stats.count = lazy.stats().count
-    package_manager_stats.time = lazy.stats().startuptime
+    local stats = lazy.stats()
+    package_manager_stats.loaded = stats.loaded
+    package_manager_stats.count = stats.count
+    package_manager_stats.time = stats.startuptime
   end
   return package_manager_stats
 end
@@ -135,7 +132,6 @@ function utils.generate_empty_table(length)
   if length == 0 then
     return empty_tbl
   end
-
   for _ = 1, length do
     table.insert(empty_tbl, '')
   end
@@ -168,7 +164,7 @@ end
 function utils.buf_is_empty(bufnr)
   bufnr = bufnr or 0
   return vim.api.nvim_buf_line_count(0) == 1
-    and vim.api.nvim_buf_get_lines(0, 0, -1, false)[1] == ''
+      and vim.api.nvim_buf_get_lines(0, 0, -1, false)[1] == ''
 end
 
 local last_footer_size = nil