Rollup merge of #94493 - oribenshir:feature/ISSUE-78543_async_fn_in_foreign_crate_diag_2, r=davidtwco

Improved diagnostic on failure to meet send bound on future in a foreign crate

Provide a better diagnostic on failure to meet send bound on futures in a foreign crate.

fixes #78543

compiler/rustc_middle/src/query/mod.rs

@@ -1969,4 +1969,10 @@ rustc_queries! {
         eval_always
         desc { "computing the backend features for CLI flags" }
     }
+
+    query generator_diagnostic_data(key: DefId) -> Option<GeneratorDiagnosticData<'tcx>> {
+        storage(ArenaCacheSelector<'tcx>)
+        desc { |tcx| "looking up generator diagnostic data of `{}`", tcx.def_path_str(key) }
+        separate_provide_extern
+    }
 }