Add a new host function for reporting fatal errors; make WASM backtraces readable when printing out errors (#10741)

* Add a new host function for reporting fatal errors

* Fix one of the wasmtime executor tests

* Have `#[runtime_interface(wasm_only)]` actually mean WASM-only, and not no_std-only

* Print out errors through `Display` instead of `Debug`

* Switch one more trait to require `Error` for its error instead of only `Debug`

* Align to review comments

substrate/client/rpc-api/src/author/error.rs

@@ -103,7 +103,7 @@ impl From<Error> for rpc::Error {
 			Error::Verification(e) => rpc::Error {
 				code: rpc::ErrorCode::ServerError(VERIFICATION_ERROR),
 				message: format!("Verification Error: {}", e).into(),
-				data: Some(format!("{:?}", e).into()),
+				data: Some(e.to_string().into()),
 			},
 			Error::Pool(PoolError::InvalidTransaction(InvalidTransaction::Custom(e))) => rpc::Error {
 				code: rpc::ErrorCode::ServerError(POOL_INVALID_TX),