feat(casan): add native plugin facade

.claude-plugin/marketplace.json

@@ -0,0 +1,37 @@
+{
+  "name": "casan",
+  "owner": {
+    "name": "CASAN Team"
+  },
+  "metadata": {
+    "description": "Native operator facade for the CASAN governed AI coding assurance runtime"
+  },
+  "plugins": [
+    {
+      "name": "casan",
+      "source": "./",
+      "description": "Adopt, diagnose, verify, and operate CASAN from Claude Code without bypassing project-local hook trust or runtime integrity controls.",
+      "version": "1.0.7",
+      "author": {
+        "name": "CASAN Team"
+      },
+      "license": "Proprietary",
+      "keywords": [
+        "agentic-coding",
+        "assurance",
+        "governance",
+        "security",
+        "audit"
+      ],
+      "category": "workflow",
+      "tags": [
+        "agentic-coding",
+        "assurance",
+        "governance",
+        "security",
+        "audit"
+      ],
+      "strict": true
+    }
+  ]
+}

.claude-plugin/plugin.json

@@ -0,0 +1,20 @@
+{
+  "name": "casan",
+  "version": "1.0.7",
+  "description": "Native Claude Code operator facade for the CASAN governed AI coding assurance runtime.",
+  "author": {
+    "name": "CASAN Team"
+  },
+  "license": "Proprietary",
+  "keywords": [
+    "claude-code",
+    "agentic-coding",
+    "assurance",
+    "governance",
+    "security",
+    "audit"
+  ],
+  "skills": [
+    "./skills/"
+  ]
+}

.codex-plugin/plugin.json

@@ -0,0 +1,30 @@
+{
+  "name": "casan",
+  "version": "1.0.7",
+  "description": "Native Codex operator facade for the CASAN governed AI coding assurance runtime.",
+  "author": {
+    "name": "CASAN Team"
+  },
+  "license": "Proprietary",
+  "keywords": [
+    "agentic-coding",
+    "assurance",
+    "governance",
+    "security",
+    "audit"
+  ],
+  "skills": "./skills/",
+  "interface": {
+    "displayName": "CASAN",
+    "shortDescription": "Governed AI coding assurance",
+    "longDescription": "Adopt, diagnose, verify, and operate the CASAN assurance runtime from Codex while preserving project-local hook trust and the versioned shared runtime.",
+    "developerName": "CASAN Team",
+    "category": "Developer Tools",
+    "capabilities": [
+      "Project adoption",
+      "Assurance verification",
+      "Governed execution"
+    ],
+    "defaultPrompt": "Use $casan to adopt and verify CASAN in this project."
+  }
+}

.gitea/workflows/ci.yml

@@ -102,6 +102,9 @@ jobs:
       - name: Prove managed and vendored Core adoption
         run: bash packages/casan-devkit/tests/hybrid-install-tests.sh
 
+      - name: Validate native Codex and Claude plugin facades
+        run: python3 packages/casan-devkit/tests/native-plugin-tests.py
+
       - name: Run adversarial harness tests (44 tests)
         run: bash packages/casan-harness/tests/adversarial-harness-tests.sh
 

.github/workflows/ci.yml

@@ -56,6 +56,8 @@ jobs:
           node-version: "20"
           cache: npm
       - run: npm ci
+      - name: Validate native Codex and Claude plugin facades
+        run: python3 packages/casan-devkit/tests/native-plugin-tests.py
       - name: Run reusable governance suites
         env:
           CASAN_CI_RUN_PROJECT: "0"

README.md

@@ -87,6 +87,33 @@ multi-project, RBAC tập trung, approvals và fleet operations.
 - Windows: PowerShell 5.1+, Python 3 và Git for Windows/Git Bash.
 - Client tương ứng nếu cần: Claude Code, Codex hoặc VS Code.
 
+### Native plugin façade — tùy chọn
+
+Repository root đồng thời là marketplace source cho Codex và Claude Code. Plugin
+chỉ cung cấp skill `$casan` để agent biết cách adopt, diagnose và verify CASAN;
+nó **không** tự bật hook, không tự cài runtime và không thay thế bước trust của
+client.
+
+Từ một checkout đã được tổ chức phê duyệt:
+
+```bash
+# Codex
+codex plugin marketplace add /absolute/path/to/CASAN
+codex plugin add casan@casan
+```
+
+Trong Claude Code:
+
+```text
+/plugin marketplace add /absolute/path/to/CASAN
+/plugin install casan@casan
+```
+
+Sau khi cài plugin, mở session mới và gọi `$casan`. Runtime production vẫn được
+cài một lần bằng `install.sh`/`install.ps1`, sau đó mỗi repository phải chạy
+`casan init`. Không cài chồng native plugin và một bản skill copy thủ công vào
+cùng client.
+
 ### 1. Cài DevKit một lần trên máy
 
 Từ checkout hoặc release bundle đã được duyệt:
@@ -611,6 +638,8 @@ Dùng explicit route `@casan <prompt>` và kiểm tra
 
 | Path | Trách nhiệm |
 |---|---|
+| `.codex-plugin/`, `.claude-plugin/` | Native marketplace manifests; không tự bật enforcement |
+| `skills/casan/` | Operator skill façade dùng chung cho Codex và Claude Code |
 | `bin/casan` | CLI entrypoint |
 | `install.sh`, `install.ps1` | Global installers |
 | `packages/casan-harness/` | Runtime controls, adapters, policies, evidence và source tests |

docs/packaging/CASAN_PACKAGING_PLAN.md

@@ -9,7 +9,7 @@ contents + maturity: [`packaging/levels.json`](../../packaging/levels.json).
 
 | Edition | Package names | Status | What it is |
 |---|---|:--:|---|
-| **1 — Core Harness** | `casan-core`, `casan-harness` | ✅ implemented | Minimal H1–H7 production runtime plus zero-dependency Local Assurance Viewer: latest/history, interactive H1–H7, H6 and on-demand export |
+| **1 — Core Harness** | `casan-core`, `casan-harness` | ✅ implemented | Minimal H1–H7 production runtime, native Codex/Claude operator façade, plus zero-dependency Local Assurance Viewer: latest/history, interactive H1–H7, H6 and on-demand export |
 | **2 — DevKit / Adoption Kit** | `casan-devkit`, `casan-project-kit` | ✅ implemented | Level 1 + project templates, domain-pack scaffold, Gitea workflow template, harness Dockerfile, install script, adoption/CI/domain-pack guides |
 | **3 — Platform Components** | `casan-platform`, `casan-control-panel` | 🟡 preview | Control Panel, Dashboard, Run History, governed chat MVP and **Evidence Pack Viewer**. Attack Battery Viewer, Gitea evidence publishing, and managed rollout are still pending. |
 | **4 — Enterprise / Governed Console** | `casan-enterprise`, `casan-governed-console` | 📋 future | Promotion layer requiring managed deployment, KMS/Object Lock operations, HA/DR/SLA, external review and compliance/support evidence. |
@@ -42,6 +42,12 @@ Docker images (see `DOCKER_GUIDE.md`): `casan-harness:X.Y.Z` ✅ · `casan-platf
 Every bundle carries `BUNDLE-MANIFEST.txt` + `SHA256SUMS`; preview bundles also carry
 `PREVIEW-INCOMPLETE.txt`.
 
+Core and every cumulative bundle also carry `.codex-plugin/`, `.claude-plugin/`
+and `skills/casan/`. These files expose an optional native `$casan` operator
+surface. They do not install the shared runtime or enable project hooks; the
+production trust path remains global/vendored runtime installation followed by
+`casan init` and client hook review.
+
 ## Production runtime boundary
 
 `packaging/runtime-layout.json` is the canonical allowlist used by macOS/Linux,
@@ -77,6 +83,9 @@ packages/casan-harness/     # L1 core (implemented)
 packages/casan-devkit/      # L2 adoption kit (implemented)
 packages/casan-platform/    # L3 structure-only (preview; README)
 packages/casan-enterprise/  # L4 structure-only (future; README)
+skills/casan/               # native operator skill shared by Codex + Claude
+.codex-plugin/              # Codex plugin manifest
+.claude-plugin/             # Claude plugin + marketplace manifests
 bin/casan                   # CLI
 scripts/package-release.sh  # release packager
 packaging/levels.json       # bundle contents + maturity (source of truth)

packages/casan-devkit/tests/hybrid-install-tests.sh

@@ -70,6 +70,10 @@ for forbidden in (
 ):
     assert not (root / forbidden).exists(), forbidden
 for required in (
+    ".codex-plugin/plugin.json",
+    ".claude-plugin/plugin.json",
+    ".claude-plugin/marketplace.json",
+    "skills/casan/SKILL.md",
     "packages/casan-harness/assets/local-viewer/index.html",
     "packages/casan-harness/assets/local-viewer/app.css",
     "packages/casan-harness/assets/local-viewer/app.js",

packages/casan-devkit/tests/native-plugin-tests.py

@@ -0,0 +1,76 @@
+#!/usr/bin/env python3
+"""Validate the repository-root CASAN native plugin facades."""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+
+ROOT = Path(__file__).resolve().parents[3]
+VERSION = (ROOT / "VERSION").read_text(encoding="utf-8").strip()
+
+
+def load_json(relative_path: str) -> dict[str, object]:
+    payload = json.loads((ROOT / relative_path).read_text(encoding="utf-8"))
+    assert isinstance(payload, dict), relative_path
+    return payload
+
+
+def main() -> None:
+    codex = load_json(".codex-plugin/plugin.json")
+    assert codex["name"] == "casan"
+    assert codex["version"] == VERSION
+    assert codex["skills"] == "./skills/"
+    assert "hooks" not in codex
+    assert codex["license"] == "Proprietary"
+
+    interface = codex["interface"]
+    assert isinstance(interface, dict)
+    for field in (
+        "displayName",
+        "shortDescription",
+        "longDescription",
+        "developerName",
+        "category",
+        "capabilities",
+        "defaultPrompt",
+    ):
+        assert interface.get(field), field
+
+    claude = load_json(".claude-plugin/plugin.json")
+    assert claude["name"] == "casan"
+    assert claude["version"] == VERSION
+    assert claude["skills"] == ["./skills/"]
+    assert "hooks" not in claude
+
+    marketplace = load_json(".claude-plugin/marketplace.json")
+    plugins = marketplace["plugins"]
+    assert isinstance(plugins, list) and len(plugins) == 1
+    entry = plugins[0]
+    assert isinstance(entry, dict)
+    assert entry["name"] == "casan"
+    assert entry["source"] == "./"
+    assert entry["version"] == VERSION
+
+    skill = (ROOT / "skills/casan/SKILL.md").read_text(encoding="utf-8")
+    assert skill.startswith("---\nname: casan\n")
+    assert "description:" in skill
+    assert "[TODO:" not in skill
+    assert (ROOT / "skills/casan/agents/openai.yaml").is_file()
+
+    levels = load_json("packaging/levels.json")
+    level_map = levels["levels"]
+    assert isinstance(level_map, dict)
+    core = level_map["core"]
+    assert isinstance(core, dict)
+    includes = core["includes"]
+    assert isinstance(includes, list)
+    for required in (".codex-plugin", ".claude-plugin", "skills"):
+        assert required in includes, required
+
+    print(f"NATIVE_PLUGIN_PASS version={VERSION} codex=true claude=true")
+
+
+if __name__ == "__main__":
+    main()

packaging/levels.json

@@ -7,9 +7,12 @@
       "level": 1,
       "package_names": ["casan-core", "casan-harness"],
       "status": "implemented",
-      "summary": "Minimal H1-H7 production runtime: security/action gates, evidence pack, audit, cost/telemetry, policy/config defaults, adapters, lightweight CLI, three-dimensional commercial readiness, and a zero-dependency single-project Local Assurance Viewer with H1-H7, H6, history and on-demand export. Source-only tests and Platform helpers are excluded.",
+      "summary": "Minimal H1-H7 production runtime: security/action gates, evidence pack, audit, cost/telemetry, policy/config defaults, adapters, lightweight CLI, native Codex/Claude operator facade, three-dimensional commercial readiness, and a zero-dependency single-project Local Assurance Viewer with H1-H7, H6, history and on-demand export. Source-only tests and Platform helpers are excluded.",
       "target_users": ["governance-harness-only projects", "BJT initial adoption", "CI gate usage"],
       "includes": [
+        ".codex-plugin",
+        ".claude-plugin",
+        "skills",
         "packages/casan-harness",
         "bin/casan",
         "install.sh",

scripts/smoke-release-artifact.sh

@@ -29,7 +29,17 @@ done < <(find "$WORK" -mindepth 1 -maxdepth 1 -type d -print)
 }
 ROOT="${roots[0]}"
 
-required=(BUNDLE-MANIFEST.txt SHA256SUMS VERSION bin/casan packages/casan-harness)
+required=(
+  BUNDLE-MANIFEST.txt
+  SHA256SUMS
+  VERSION
+  bin/casan
+  packages/casan-harness
+  .codex-plugin/plugin.json
+  .claude-plugin/plugin.json
+  .claude-plugin/marketplace.json
+  skills/casan/SKILL.md
+)
 for path in "${required[@]}"; do
   [[ -e "$ROOT/$path" ]] || {
     echo "ARTIFACT_SMOKE_FAIL reason=required_path_missing path=$path" >&2

skills/casan/SKILL.md

@@ -0,0 +1,58 @@
+---
+name: casan
+description: Operate the CASAN governed AI coding assurance runtime. Use when adopting CASAN into a repository, configuring Claude Code or Codex hooks, checking readiness or runtime integrity, running governance gates, inspecting assurance reports, exporting evidence, or diagnosing CASAN installation and enforcement problems.
+---
+
+# CASAN
+
+Use the installed CASAN CLI as the only operational entry point. This skill is
+an operator facade; it does not duplicate the assurance kernel and installing
+the plugin alone does not enable enforcement.
+
+## Resolve the runtime
+
+1. Work from the target repository root.
+2. Resolve `casan` with `command -v casan`.
+3. If it is unavailable, report that the DevKit runtime must be installed. Do
+   not install into the user's home directory unless the user explicitly asks.
+4. If the current checkout is the CASAN source hub and installation is
+   requested, use `sh install.sh --level devkit` on macOS/Linux or
+   `pwsh ./install.ps1` on Windows.
+5. Never treat plugin registration as proof that project hooks or enforcement
+   are active.
+
+## Route the request
+
+- Adopt or reconfigure a repository: run `casan init`. Preserve an existing
+  runtime and enforcement choice unless the user explicitly changes it.
+- Configure automation: run `casan init --non-interactive --edition core
+  --runtime managed --mode enforce --client claude,codex` and adjust only the
+  options the user requested.
+- Diagnose an installation or project: run `casan doctor`, then
+  `casan readiness --refresh` and `casan verify-harness` as needed.
+- Verify governance: run `casan gate` for project checks and `casan verify` for
+  audit, tool, and policy verification.
+- Inspect evidence: use `casan report latest`, `casan view`, or
+  `casan report export` according to the requested output.
+- Inspect the product selection: use `casan edition show`. Do not equate an
+  installed edition with CASAN Maturity L1-L5.
+
+## Preserve the trust boundary
+
+- Check `.casan/config.json`, `.casan/version.lock`, and the selected client
+  hook projection before claiming CASAN is active.
+- Require the user to review and trust native client hooks where the client
+  exposes a trust step.
+- Never edit `version.lock` to suppress integrity drift. Restore or reinstall
+  the approved runtime and rerun `casan verify-harness`.
+- Never silently change `observe` to `enforce`, switch managed/vendored mode,
+  or enable additional client integrations.
+- Keep generated evidence and state in the target project. Do not write runtime
+  state into the plugin cache or global version directory.
+
+## Report results
+
+State the resolved runtime, project edition, enforcement mode, configured
+clients, commands run, and any failing assurance control. Distinguish a missing
+optional Domain Pipeline or provider telemetry integration from a failed Core
+assurance control.

skills/casan/agents/openai.yaml

@@ -0,0 +1,4 @@
+interface:
+  display_name: "CASAN"
+  short_description: "Governed AI coding with CASAN assurance"
+  default_prompt: "Use $casan to adopt and verify CASAN in this project."