[clang] [clang][Sema] Suggest/Hint Standard Library Include File (PR #146227)

[Erich Keane via cfe-commits]

================
@@ -5990,6 +5990,10 @@ def err_template_expansion_into_fixed_list : Error<
   "template|concept}0">;
 def note_parameter_type : Note<
   "parameter of type %0 is declared here">;
+def note_standard_lib_include_suggestion : Note<
+  "maybe try to include %0; '%1' is defined in %0">;
----------------
erichkeane wrote:

```suggestion
  "'%1' is defined in %0; did you mean to include it?">;
```

https://github.com/llvm/llvm-project/pull/146227