feat: add product-forge extension to community catalog (#2012)

Product Forge — Full product lifecycle SpecKit extension by VaiYav.
Covers 9 phases: research → product-spec → revalidation → bridge →
plan → implement → verify → test-plan → test-run.

10 commands, MIT license, v1.1.0
https://github.com/VaiYav/speckit-product-forge

Co-authored-by: Valentyn Yakovliev <your-verified-email@example.com>

extensions/catalog.community.json

@@ -1,6 +1,6 @@
 {
   "schema_version": "1.0",
-  "updated_at": "2026-03-27T08:22:30Z",
+  "updated_at": "2026-03-28T00:00:00Z",
   "catalog_url": "https://raw.githubusercontent.com/github/spec-kit/main/extensions/catalog.community.json",
   "extensions": {
     "aide": {
@@ -789,6 +789,38 @@
       "created_at": "2026-03-18T00:00:00Z",
       "updated_at": "2026-03-18T00:00:00Z"
     },
+    "product-forge": {
+      "name": "Product Forge",
+      "id": "product-forge",
+      "description": "Full product lifecycle: research \u2192 product spec \u2192 SpecKit \u2192 implement \u2192 verify \u2192 test",
+      "author": "VaiYav",
+      "version": "1.1.1",
+      "download_url": "https://github.com/VaiYav/speckit-product-forge/archive/refs/tags/v1.1.1.zip",
+      "repository": "https://github.com/VaiYav/speckit-product-forge",
+      "homepage": "https://github.com/VaiYav/speckit-product-forge",
+      "documentation": "https://github.com/VaiYav/speckit-product-forge/blob/main/README.md",
+      "changelog": "https://github.com/VaiYav/speckit-product-forge/blob/main/CHANGELOG.md",
+      "license": "MIT",
+      "requires": {
+        "speckit_version": ">=0.1.0"
+      },
+      "provides": {
+        "commands": 10,
+        "hooks": 0
+      },
+      "tags": [
+        "process",
+        "research",
+        "product-spec",
+        "lifecycle",
+        "testing"
+      ],
+      "verified": false,
+      "downloads": 0,
+      "stars": 0,
+      "created_at": "2026-03-28T00:00:00Z",
+      "updated_at": "2026-03-28T00:00:00Z"
+    },
     "ralph": {
       "name": "Ralph Loop",
       "id": "ralph",