feat: Add DocGuard CDD enforcement extension to community catalog (#1838)

* feat: add DocGuard CDD enforcement extension to community catalog

DocGuard is a Canonical-Driven Development enforcement tool that generates,
validates, scores, and traces project documentation against 51 automated checks.

Provides 6 commands:
- guard: 51-check validation with quality labels
- diagnose: AI-ready fix prompts
- score: CDD maturity scoring (0-100)
- trace: ISO 29119 traceability matrix
- generate: Reverse-engineer docs from codebase
- init: Initialize CDD with compliance profiles

Features:
- Zero dependencies (pure Node.js)
- Config-aware traceability (respects .docguard.json)
- Orphan file detection
- Research-backed (AITPG/TRACE, IEEE TSE/TMLCN 2026)

npm: https://www.npmjs.com/package/docguard-cli
GitHub: https://github.com/raccioly/docguard

* fix: use release asset URL for download_url

The source archive URL nests files under a subdirectory, so the
Spec Kit installer cannot find extension.yml at the archive root.
Switch to a release asset ZIP built from the extension directory.

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* docs: add DocGuard to community extensions README table

* chore: update DocGuard entry to v0.8.0 (92 checks)

* chore: update DocGuard description (51→92 checks)

---------

Co-authored-by: Ricardo Accioly <ricardoaccioly@RAccioly-J0CWDQ4MXV.attlocal.net>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

extensions/catalog.community.json

@@ -74,6 +74,48 @@
       "created_at": "2026-02-22T00:00:00Z",
       "updated_at": "2026-02-22T00:00:00Z"
     },
+    "docguard": {
+      "name": "DocGuard — CDD Enforcement",
+      "id": "docguard",
+      "description": "Canonical-Driven Development enforcement. Generates, validates, scores, and traces project documentation against 92 automated checks. Zero dependencies.",
+      "author": "raccioly",
+      "version": "0.8.0",
+      "download_url": "https://github.com/raccioly/docguard/releases/download/v0.8.0/spec-kit-docguard-v0.8.0.zip",
+      "repository": "https://github.com/raccioly/docguard",
+      "homepage": "https://www.npmjs.com/package/docguard-cli",
+      "documentation": "https://github.com/raccioly/docguard/blob/main/extensions/spec-kit-docguard/README.md",
+      "changelog": "https://github.com/raccioly/docguard/blob/main/CHANGELOG.md",
+      "license": "MIT",
+      "requires": {
+        "speckit_version": ">=0.1.0",
+        "tools": [
+          {
+            "name": "node",
+            "version": ">=18.0.0",
+            "required": true
+          }
+        ]
+      },
+      "provides": {
+        "commands": 6,
+        "hooks": 1
+      },
+      "tags": [
+        "documentation",
+        "validation",
+        "quality",
+        "cdd",
+        "traceability",
+        "ai-agents",
+        "enforcement",
+        "scoring"
+      ],
+      "verified": false,
+      "downloads": 0,
+      "stars": 0,
+      "created_at": "2026-03-13T00:00:00Z",
+      "updated_at": "2026-03-13T00:00:00Z"
+    },
     "doctor": {
       "name": "Project Health Check",
       "id": "doctor",
@@ -124,7 +166,12 @@
         "commands": 2,
         "hooks": 1
       },
-      "tags": ["orchestration", "workflow", "human-in-the-loop", "parallel"],
+      "tags": [
+        "orchestration",
+        "workflow",
+        "human-in-the-loop",
+        "parallel"
+      ],
       "verified": false,
       "downloads": 0,
       "stars": 0,
@@ -191,7 +238,12 @@
         "commands": 2,
         "hooks": 1
       },
-      "tags": ["implementation", "automation", "loop", "copilot"],
+      "tags": [
+        "implementation",
+        "automation",
+        "loop",
+        "copilot"
+      ],
       "verified": false,
       "downloads": 0,
       "stars": 0,
@@ -249,7 +301,15 @@
         "commands": 7,
         "hooks": 1
       },
-      "tags": ["code-review", "quality", "review", "testing", "error-handling", "type-design", "simplification"],
+      "tags": [
+        "code-review",
+        "quality",
+        "review",
+        "testing",
+        "error-handling",
+        "type-design",
+        "simplification"
+      ],
       "verified": false,
       "downloads": 0,
       "stars": 0,