update future.{write,read} ABIs

This updates the plumbing, FACT, compilation, and runtime code to use the new
ABI defined in WebAssembly/component-model#524.

- `future.write` now accepts its payload value as up to 4 flat parameters before spilling to linear memory.

- `future.read` takes no payload pointer when it has no payload type

- `{stream,future}.close-{readable,writable}` have been renamed to `{stream,future}.drop-{readable,writable}`

This commit does _not_ address the following items:

> * There is no "number of elements written" packed in the high 28 bits of the `future.{read,write}` results.
> * On successful copy, `future.{read,write}` return `COMPLETED` instead of `CLOSED` (which, as noted above, was renamed to `DROPPED`, making it especially "wrong" as the result code).
> * When a `future` is "done" (by a `COMPLETED` read/write or by the writable end receiving `DROPPED`), the only valid operation is `future.drop-{readable,writable}`.  `future.{read,write}` or lifting traps.
> * Because there's no great reason for streams to be more permissive than futures in this regard, streams are also given a "done" state with the same trapping rules as futures, but the stream "done" state is only set when `DROPPED` is received.

I'll address those in one or more follow-up commits.

Signed-off-by: Joel Dice <[email protected]>

Author: dicej