contracts: Change define_env! to expect a Result<T, DispatchError> for every function (#7762)

* Make host functions return TrapReason

This avoids the need to manually store any trap reasons
to the `Runtime` from the host function. This adds the following
benefits:

* It properly composes with the upcoming chain extensions
* Missing to set a trap value is now a compile error

* review: Remove superflous .into()

substrate/frame/contracts/src/lib.rs

@@ -378,6 +378,14 @@ decl_error! {
 		/// on the call stack. Those actions are contract self destruction and restoration
 		/// of a tombstone.
 		ReentranceDenied,
+		/// `seal_input` was called twice from the same contract execution context.
+		InputAlreadyRead,
+		/// The subject passed to `seal_random` exceeds the limit.
+		RandomSubjectTooLong,
+		/// The amount of topics passed to `seal_deposit_events` exceeds the limit.
+		TooManyTopics,
+		/// The topics passed to `seal_deposit_events` contains at least one duplicate.
+		DuplicateTopics,
 	}
 }