feat(package): add component and WIT package tooling

- define the constrained .wasmpkg archive and integrity checks\n- encode and inspect standard binary WIT packages\n- resolve exact Registry dependencies with wit.lock and path replace\n- provide wasmeld pack and wit build/fetch/publish CLI commands

Cargo.toml

@@ -0,0 +1,23 @@
+[workspace]
+members = [
+  "crates/wasmeld-package",
+]
+default-members = ["crates/wasmeld-package"]
+resolver = "2"
+
+[workspace.package]
+edition = "2024"
+rust-version = "1.90"
+license = "Apache-2.0"
+
+[workspace.dependencies]
+reqwest = { version = "0.13.4", default-features = false, features = ["blocking", "json", "multipart", "rustls"] }
+serde = { version = "1.0.228", features = ["derive"] }
+serde_json = "1.0.149"
+semver = "1.0.28"
+sha2 = "0.10.9"
+thiserror = "2.0.17"
+toml = "0.9.8"
+wit-component = "=0.243.0"
+wit-parser = "0.243.0"
+zip = { version = "2.4.2", default-features = false, features = ["deflate"] }