Add z4code agent

[zeta9044]

Add z4code agent

This PR registers z4code in the Agent Client Protocol registry.

z4code is a local-model coding agent for Zed. It talks to Zed over ACP and is designed to run against locally hosted models.

What makes z4code distinctive

z4code ships with specialized skills built by zeta4lab for developing zeta4lab's own products:

• zeta4g — a skill for building GraphRAG databases: ontology design, entity/relation extraction, graph storage, and graph-native retrieval.
• zeta4s — a skill for building step-graph workflows: modeling and orchestrating multi-step, graph-structured execution.

These skills let z4code act as a domain-aware coding partner for the zeta4 stack, not just a generic coding agent.

Links

• Showcase: https://showcase.zeta4.net
• zeta4lab: https://zeta4.net

Changes

• z4code/agent.json — agent manifest: id z4code, version 0.6.0, Apache-2.0 license, repository link, and a darwin-aarch64 binary distribution entry (archive URL + SHA-256 checksum, launched via z4code acp).
• z4code/icon.svg — 16×16 monochrome icon.

Details

• Repository: https://github.com/zeta4lab/z4code
• Version: 0.6.0
• License: Apache-2.0
• Distribution: prebuilt darwin-aarch64 binary

Status

This is an early release (0.6.0); further stabilization is ongoing.

[zeta9044]

Updated the entry: repository now points at the public binary distribution repository and a website field was added.

The z4code source repository is private, so the previous repository URL returned 404 for anyone visiting the entry. The archive URL, SHA-256, version, cmd, and args are unchanged — the published artifact itself is untouched.

build_registry.py --dry-run validates the entry locally (with the expected "missing builds for: linux, windows" warning; macOS arm64 is the only supported target).

[zeta9044]

Added Linux and Windows binaries.

Release 0.6.0 now publishes four archives built from the same tagged sources, each with its exact published SHA-256:

Platform	Archive
darwin-aarch64	z4code-aarch64-apple-darwin.zip
linux-x86_64	z4code-x86_64-unknown-linux-gnu.zip
linux-aarch64	z4code-aarch64-unknown-linux-gnu.zip
windows-x86_64	z4code-x86_64-pc-windows-msvc.zip

The macOS archive and its digest are unchanged from the original submission.

build_registry.py --dry-run validates the entry, and the earlier "missing builds for: linux, windows" warning is gone. Every archive URL was downloaded unauthenticated and its digest reproduced against the manifest.