feat(publish): allow directory path for wkg publish

[mkatychev]

Moved parts of wkg wit build into shared function to allow logic reuse between publish and build:

wasm-pkg-tools/crates/wkg/src/wit.rs

Lines 113 to 124 in a840224

	/// Build a WIT package from a directory, returning the resolved package ref, optional
	/// version, and the encoded component bytes.
	pub async fn build_wit_dir(
	dir: impl AsRef<Path>,
	client: CachingClient<FileCache>,
	mut lock_file: &mut LockFile,
	) -> anyhow::Result<(PackageRef, Option<Version>, Vec<u8>)> {
	check_dir(&dir).await?;
	let wkg_config = wasm_pkg_core::config::Config::load().await?;
	let result = wit::build_package(&wkg_config, dir, &mut lock_file, client).await?;
	Ok(result)
	}

wkg publish ./wit/ will abort if it would result in changing wkg.lock

[mkatychev]

I'm not sure this check is even needed yet

[vados-cosmonic]

Hey @mkatychev this looks great!

Either in this PR or as a follow up (this PR has certainly been waiting too long!), what do you think about adding a regression test for this real quick? If there are any convenient-to-add adjacent tests those would be great too, but reading over the code this makes me think that we should really be testing the at multiple levels (core/client & CLI) to make sure we don't regress.

[mkatychev]

@vados-cosmonic I agree, one of my hesitations in doing config/data driven coverage testing is that I plan to add overlay support cargo style sometime after #215. Note this commit from the multi package publishing PR:

https://github.com/mkatychev/wasm-pkg-tools/blob/9de6af4ed5fad54b71f7ccb8b8e77b953e0910c5/crates/wkg/src/main.rs#L273-L304