vera run prints 0 for a function returning bare Future<String> (display-only)

`vera run --fn mk` on a function returning a **bare** `Future<String>` prints `0` instead of the string value. The emitted WASM is sound (a caller that awaits the result gets the right value); the defect is display-only: `_return_type_is_string` (vera/codegen/core.py:1249) name-matches `String` without the `Future<...>` strip, so `execute()` doesn't decode the returned (ptr, len) pair for the transparent wrapper. Minor (CLI display), but the same Future-transparency family as #1031/#1037/#1038/#1039. Found by the adversarial review of #1041.