feat: add binary type support for host functions (#40)

* feat: add binary type support for host functions

Adds Uint8Array/Buffer support for host function arguments and returns.

Architecture:
- New hyperlight-js-common crate: shared wire-format constants, binary
  sidecar encode/decode, FnReturn enum, DecodeError type
- Guest extracts Uint8Array from QuickJS VM into binary sidecar
- Host dispatches via register() (typed serde) or register_js() (JS bridge)
- NAPI layer creates native Node.js Buffers via C API (no base64)
- Tagged return format (0x00=JSON, 0x01=binary) for return path

Key changes:
- Single CallHostJsFunction entry point (removed legacy JSON-only path)
- Native Buffer marshalling in NAPI (JsArg/JsReturn types)
- Depth limits on all recursive JSON tree traversals (MAX_JSON_DEPTH=64)
- Trailing data rejection in sidecar decoder
- Typed register() rejects binary args with clear error message
- Comprehensive test coverage (Rust unit + integration + JS vitest)
- Updated README with Binary Data section and wire protocol docs
- Updated CI publish order for new common crate

Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

* Apply suggestions from code review

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

* Apply suggestions from code review

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

* Update src/js-host-api/src/lib.rs

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

* fix: address PR review comments

- Fix napi_create_string_utf8 length parameter cast (isize  usize)
- Fix formatted error string using concat!() to avoid embedded whitespace

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

---------

Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: 3 people

Cargo.lock

@@ -1,6 +1,6 @@
 [workspace]
 resolver = "2"
-members = ["src/hyperlight-js", "src/js-host-api", "src/hyperlight-js-runtime"]
+members = ["src/hyperlight-js", "src/js-host-api", "src/hyperlight-js-runtime", "src/hyperlight-js-common"]
 
 [workspace.package]
 version = "0.3.0"
@@ -13,9 +13,12 @@ readme = "README.md"
 [workspace.dependencies]
 hyperlight-guest-bin = { version = "0.16.0", features = ["libc"] }
 hyperlight-host = { version = "0.16.0", default-features = false }
+hyperlight-common = { version = "0.16.0", default-features = false }
+hyperlight-guest = { version = "0.16.0" }
 
 hyperlight-js = { version = "0.3.0", path = "src/hyperlight-js" }
 hyperlight-js-runtime = { version = "0.3.0", path = "src/hyperlight-js-runtime" }
+hyperlight-js-common = { version = "0.3.0", path = "src/hyperlight-js-common" }
 
 [profile.dev]
 panic = "abort"

Cargo.toml

@@ -51,7 +51,7 @@ When this job is done, a new [GitHub release](https://github.com/hyperlight-dev/
 
 This release contains the benchmark results and the source code for the release along with automatically generated release notes.
 
-In addition the hyperlight-js crates will be published to crates.io. You can verify this by going to the [hyperlight-js page on crates.io](https://crates.io/crates/hyperlight-js) and checking that the new version is listed.
+In addition, the hyperlight-js crates will be published to crates.io in dependency order (`hyperlight-js-common` → `hyperlight-js-runtime` → `hyperlight-js`). You can verify this by going to the [hyperlight-js page on crates.io](https://crates.io/crates/hyperlight-js) and checking that the new version is listed.
 
 The npm packages (`@hyperlight-dev/js-host-api` and platform-specific binaries) are also published automatically as part of this workflow. Publishing uses [npm trusted publishing (OIDC)](https://docs.npmjs.com/trusted-publishers) — no `NPM_TOKEN` secret is needed for the `CreateRelease` workflow. Provenance attestations are generated automatically.
 

docs/release.md

@@ -0,0 +1,18 @@
+[package]
+name = "hyperlight-js-common"
+version.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+license.workspace = true
+repository.workspace = true
+readme.workspace = true
+description = """
+Shared constants and binary framing utilities for hyperlight-js.
+
+This crate is `no_std`-compatible (with `alloc`) so it can be used by both
+the host-side `hyperlight-js` crate and the guest-side `hyperlight-js-runtime`
+crate (which compiles for `x86_64-hyperlight-none`).
+"""
+
+[dependencies]
+# no_std + alloc only — no std, no serde, no anyhow