canary

fix stream/future tests to handle actual asynchrony (#179)

Due to the `wit-dylib` issue that
https://github.com/bytecodealliance/wasm-tools/pull/2371 addresses, these tests
weren't actually testing what I thought they were.  Fixing that revealed a
couple of bugs involving stream writes, which this fixes.

Also, bump version to 0.19.2

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