LunaPack 0.1.2

LunaPack 0.1.2

The package now builds on moonbitlang/core/async, which the MoonBit
developers have confirmed the stable releases will use. The wrapper
package moonbitlang/async was already built on the core one, so this
removes a layer instead of adding a risk.

The package has no dependencies at all now: moon.mod declares none,
nothing is vendored, nothing has to be resolved when the published
module is fetched, and the CI no longer contacts the registry.

The packages are unchanged. The archive built by the old and the new
implementation is byte-identical apart from the creation time in the
manifest, the gzip streams included, and every entry agrees on its size,
mode, checksum and fingerprint.

The API differences were mechanical:

• fs.read_file(p).binary() -> fs.read_binary(p)
• fs.write_file(p, bytes) -> fs.write_binary(p), write_text(p, s)
• the io traits are BinaryReader and BinaryWriter now
• the gzip decoder returns the bytes directly

30/30 tests pass on the native and the wasm backend.