feat: new config with everything manually installed

lsp/clangd.lua

@@ -0,0 +1,5 @@
+return {
+    cmd = { 'clangd' },
+    filetypes = { 'c', 'cpp', 'objc', 'objcpp' },
+    root_markers = { 'compile_commands.json', '.git', 'compile_flags.txt' },
+}