Add V-Model Extension Pack to catalog (#1640)

* Add V-Model Extension Pack to catalog

Second community extension: V-Model paired dev-spec and test-spec
generation with regulatory-grade traceability.

- 3 commands: requirements, acceptance, trace
- Deterministic coverage validation (regex-based, not AI)
- Targets: IEC 62304, ISO 26262, DO-178C, FDA 21 CFR Part 820
- Repository: https://github.com/leocamello/spec-kit-v-model
- Release: v0.1.0

* Fix catalog entry: provides as number, add timestamps and statistics

Address review feedback:
- provides.commands: array → number (3), add hooks (1)
- Add created_at and updated_at timestamps
- Add statistics block (downloads: 0, stars: 0)

* Address review: use catalog.community.json and add extensions README

Per maintainer feedback:
- Revert catalog.json to its original empty state (empty by design)
- Rename catalog.example.json → catalog.community.json
- Replace example entries with real V-Model Extension Pack entry
- Add extensions/README.md with community extensions table

extensions/README.md

@@ -0,0 +1,13 @@
+# Spec Kit Community Extensions
+
+Community-contributed extensions for [Spec Kit](https://github.com/github/spec-kit).
+
+## Available Extensions
+
+| Extension | Purpose | URL |
+|-----------|---------|-----|
+| V-Model Extension Pack | Enforces V-Model paired generation of development specs and test specs with full traceability | [spec-kit-v-model](https://github.com/leocamello/spec-kit-v-model) |
+
+## Adding Your Extension
+
+See the [Extension Publishing Guide](EXTENSION-PUBLISHING-GUIDE.md) for instructions on how to submit your extension to the community catalog.

extensions/catalog.community.json

@@ -0,0 +1,33 @@
+{
+  "schema_version": "1.0",
+  "updated_at": "2026-02-20T00:00:00Z",
+  "catalog_url": "https://raw.githubusercontent.com/github/spec-kit/main/extensions/catalog.community.json",
+  "extensions": {
+    "v-model": {
+      "name": "V-Model Extension Pack",
+      "id": "v-model",
+      "description": "Enforces V-Model paired generation of development specs and test specs with full traceability.",
+      "author": "leocamello",
+      "version": "0.1.0",
+      "download_url": "https://github.com/leocamello/spec-kit-v-model/archive/refs/tags/v0.1.0.zip",
+      "repository": "https://github.com/leocamello/spec-kit-v-model",
+      "homepage": "https://github.com/leocamello/spec-kit-v-model",
+      "documentation": "https://github.com/leocamello/spec-kit-v-model/blob/main/README.md",
+      "changelog": "https://github.com/leocamello/spec-kit-v-model/blob/main/CHANGELOG.md",
+      "license": "MIT",
+      "requires": {
+        "speckit_version": ">=0.1.0"
+      },
+      "provides": {
+        "commands": 3,
+        "hooks": 1
+      },
+      "tags": ["v-model", "traceability", "testing", "compliance", "safety-critical"],
+      "verified": false,
+      "downloads": 0,
+      "stars": 0,
+      "created_at": "2026-02-20T00:00:00Z",
+      "updated_at": "2026-02-20T00:00:00Z"
+    }
+  }
+}

extensions/catalog.example.json

@@ -1,60 +0,0 @@
-{
-  "schema_version": "1.0",
-  "updated_at": "2026-02-03T00:00:00Z",
-  "catalog_url": "https://your-org.example.com/speckit/catalog.json",
-  "extensions": {
-    "jira": {
-      "name": "Jira Integration",
-      "id": "jira",
-      "description": "Create Jira Epics, Stories, and Issues from spec-kit artifacts",
-      "author": "Your Organization",
-      "version": "2.1.0",
-      "download_url": "https://github.com/your-org/spec-kit-jira/archive/refs/tags/v2.1.0.zip",
-      "repository": "https://github.com/your-org/spec-kit-jira",
-      "homepage": "https://github.com/your-org/spec-kit-jira",
-      "documentation": "https://github.com/your-org/spec-kit-jira/blob/main/README.md",
-      "changelog": "https://github.com/your-org/spec-kit-jira/blob/main/CHANGELOG.md",
-      "license": "MIT",
-      "requires": {
-        "speckit_version": ">=0.1.0",
-        "tools": [
-          {
-            "name": "atlassian",
-            "version": ">=1.0.0",
-            "required": true
-          }
-        ]
-      },
-      "provides": {
-        "commands": 3,
-        "hooks": 1
-      },
-      "tags": ["jira", "atlassian", "issue-tracking"],
-      "verified": true,
-      "downloads": 0,
-      "stars": 0,
-      "created_at": "2026-01-28T00:00:00Z",
-      "updated_at": "2026-02-03T00:00:00Z"
-    },
-    "linear": {
-      "name": "Linear Integration",
-      "id": "linear",
-      "description": "Sync specs and tasks with Linear issues",
-      "author": "Your Organization",
-      "version": "1.0.0",
-      "download_url": "https://github.com/your-org/spec-kit-linear/archive/refs/tags/v1.0.0.zip",
-      "repository": "https://github.com/your-org/spec-kit-linear",
-      "license": "MIT",
-      "requires": {
-        "speckit_version": ">=0.1.0"
-      },
-      "provides": {
-        "commands": 2
-      },
-      "tags": ["linear", "issue-tracking"],
-      "verified": false,
-      "created_at": "2026-01-30T00:00:00Z",
-      "updated_at": "2026-01-30T00:00:00Z"
-    }
-  }
-}