feat!: Neural Codex port for OpenCode 1.18.31

[brolag]

Current status

This PR ports the Neural Codex evidence-gated workflow into Neural OpenCode as a lightweight OpenCode 1.18.31 harness. The supported product is now:

/discover -> /spec -> /craft -> /vet + /exercise

plus reviewed lifecycle hooks. The 1.9.0 kitchen sink is archived under archived/v1.9.0/ and is no longer presented as the supported product.

Automated checks that hold on this revision:

• python3 -m pytest -q (24 tests)
• node --test tests/hooks.test.js (8 tests)
• ./scripts/doc-lint.sh

No release tag, npm publish, or live GitHub Pages enablement was performed.

Breaking changes vs neural-open-code 1.9.0

This is a 2.0 breaking cleanup, same spirit as neural-codex 1.0.

Removed from the supported path (kept only as unsupported archive):

• Agentic course (/course) and lesson pack
• Neural Squad (/squad-*)
• Neural loops (/loop and related commands)
• TTS / ElevenLabs
• Multi-AI mesh (/pv-mesh, /ai-collab, dedicated Codex/Gemini agents)
• KPI, Compute Advantage, and cost trackers
• Memory / expertise / remember-recall product
• Skills manager, onboard tour, extra command/agent packs
• Custom install.sh / one-liner home-directory installers
• Output styles, status lines, expertise schemas, and CRAFT templates as first-class surface

Install is now two reversible project keys in opencode.json. The plugin does not mutate global model, approval, MCP, or sandbox config.

OpenCode 1.18.31 APIs used

Investigated against anomalyco/opencode tag v1.18.31. There is no OpenCode v2.0.8.

Surface	API used
Plugin package	package.json with exports["./server"], engines.opencode: ">=1.18.31"
Plugin load	project plugin array (./plugins/neural-open-code)
Skills	SKILL.md trees + skills.paths (OpenCode has no marketplace / plugin.json skill manifest)
Slash commands	skills auto-register as /discover, /spec, /craft, /vet, /exercise
Hooks	tool.execute.before, tool.execute.after, experimental.session.compacting
Tool IDs	bash, write, edit, apply_patch
Compact rules	optional AGENTS.md snippet only; the plugin does not inject system prompt

There is no hooks.json and no hook-trust UI at this tag. Blocking is a thrown error from tool.execute.before. Review plugins/neural-open-code/hooks/ before keeping the plugin entry.

Intentionally deferred

• Lyft / Lyfter integrations
• WordPress integrations
• MCP servers or MCP-dependent features
• Re-shipping 1.9.0 feature packs as supported surface
• Publishing a release, npm package, or forcing GitHub Pages live

Next steps for Alfredo

1. Review this draft PR and the hook source.
2. Merge when satisfied.
3. Enable GitHub Pages on the updated index.html / docs/ sources if you want the public site live.
4. Cut a v2.0.0 release tag when you are ready — do not treat this PR as a published release.

Install reminder after merge:

{
  "$schema": "https://opencode.ai/config.json",
  "plugin": ["./plugins/neural-open-code"],
  "skills": {
    "paths": ["./plugins/neural-open-code/skills"]
  }
}

Requires OpenCode v1.18.31 or later. Remove those two keys to uninstall.