fix(clangd): file detection improvements (#6436)

## Description

As discussed in
23b9cdeb34 (r165937336),
it'd be better to remove clang configuration files from influencing root
dir detection. I've also added meson and ninja files to the extra's
recommendation detection

## Related Issue(s)

## Screenshots

## Checklist

- [x] I've read the
[CONTRIBUTING](https://github.com/LazyVim/LazyVim/blob/main/CONTRIBUTING.md)
guidelines.

lua/lazyvim/plugins/extras/lang/clangd.lua

@@ -9,6 +9,8 @@ return {
         "compile_commands.json",
         "compile_flags.txt",
         "configure.ac", -- AutoTools
+        "meson.build",
+        "build.ninja",
       },
     })
   end,
@@ -61,9 +63,6 @@ return {
             { "<leader>ch", "<cmd>ClangdSwitchSourceHeader<cr>", desc = "Switch Source/Header (C/C++)" },
           },
           root_markers = {
-            ".clangd",
-            ".clang-tidy",
-            ".clang-format",
             "compile_commands.json",
             "compile_flags.txt",
             "configure.ac", -- AutoTools