feat!(nvim): Migrate to v0.11 built-in lsp configs

tools/nvim/lsp/clangd.lua

@@ -1,5 +1,30 @@
+-- C/C++
+-- Clangd requires compile_commands.json to work and the easiest way to generate it is to use CMake.
+-- How to use clangd C/C++ LSP in any project: https://gist.github.com/Strus/042a92a00070a943053006bf46912ae9
+
 return {
-  cmd = { "clangd", "--background-index" },
-  root_markers = { "compile_commands.json", "compile_flags.txt", ".clangd" },
+  cmd = {
+    "clangd",
+    "--clang-tidy",
+    "--header-insertion=iwyu",
+    "--completion-style=detailed",
+    "--function-arg-placeholders",
+    "--fallback-style=none",
+  },
   filetypes = { "c", "cpp" },
+  root_markers = {
+    ".clangd",
+    ".clang-format",
+    "compile_commands.json",
+    "compile_flags.txt",
+    ".git",
+  },
+  capabilities = {
+    textDocument = {
+      completion = {
+        editsNearCursor = true,
+      },
+    },
+    offsetEncoding = { "utf-8", "utf-16" },
+  },
 }