feat(catalog): add Cost Tracker (cost) community extension (#2448)

* feat(catalog): add Cost Tracker (cost) community extension

Adds a new entry for spec-kit-cost — track real LLM dollar cost across
SDD workflows with per-feature budgets, per-integration comparison,
and finance-ready exports.

Repo: https://github.com/Quratulain-bilal/spec-kit-cost
Release: v1.0.0

* docs(catalog): add Cost Tracker README row, bump updated_at

Address Copilot review feedback:
- Add Cost Tracker row to README community extensions table
- Bump top-level updated_at per EXTENSION-PUBLISHING-GUIDE.md

* fix(catalog): address Copilot feedback on cost extension entry

- Move cost entry after confluence so the c* block is alphabetized
- Bump top-level updated_at to 2026-05-05 per EXTENSION-PUBLISHING-GUIDE
- Use documented 'visibility' category in README (not 'analytics'),
  matching Token Consumption Analyzer's classification
- Replace 'analytics' tag with 'visibility' in catalog tags for consistency

* fix(catalog): bump top-level updated_at for cost entry addition

Address Copilot feedback: the file-level updated_at must be bumped on
every catalog change per EXTENSION-PUBLISHING-GUIDE.md:204-205.

---------

Co-authored-by: Quratulain-bilal <quratulain.bilal@users.noreply.github.com>

extensions/catalog.community.json

@@ -1,6 +1,6 @@
 {
   "schema_version": "1.0",
-  "updated_at": "2026-05-05T07:26:00Z",
+  "updated_at": "2026-05-06T00:00:00Z",
   "catalog_url": "https://raw.githubusercontent.com/github/spec-kit/main/extensions/catalog.community.json",
   "extensions": {
     "aide": {
@@ -580,6 +580,38 @@
       "created_at": "2026-03-29T00:00:00Z",
       "updated_at": "2026-03-29T00:00:00Z"
     },
+    "cost": {
+      "name": "Cost Tracker",
+      "id": "cost",
+      "description": "Track real LLM dollar cost across SDD workflows — per-feature budgets, per-integration comparison, and finance-ready exports.",
+      "author": "Quratulain-bilal",
+      "version": "1.0.0",
+      "download_url": "https://github.com/Quratulain-bilal/spec-kit-cost/archive/refs/tags/v1.0.0.zip",
+      "repository": "https://github.com/Quratulain-bilal/spec-kit-cost",
+      "homepage": "https://github.com/Quratulain-bilal/spec-kit-cost",
+      "documentation": "https://github.com/Quratulain-bilal/spec-kit-cost/blob/main/README.md",
+      "changelog": "https://github.com/Quratulain-bilal/spec-kit-cost/blob/main/CHANGELOG.md",
+      "license": "MIT",
+      "requires": {
+        "speckit_version": ">=0.8.0"
+      },
+      "provides": {
+        "commands": 5,
+        "hooks": 0
+      },
+      "tags": [
+        "cost",
+        "budget",
+        "tokens",
+        "visibility",
+        "finance"
+      ],
+      "verified": false,
+      "downloads": 0,
+      "stars": 0,
+      "created_at": "2026-05-03T00:00:00Z",
+      "updated_at": "2026-05-05T00:00:00Z"
+    },
     "diagram": {
       "name": "Spec Diagram",
       "id": "diagram",
@@ -2905,7 +2937,7 @@
       "downloads": 0,
       "stars": 0,
       "created_at": "2026-04-13T00:00:00Z",
-      "updated_at": "2026-04-13T00:00:00Z"      
+      "updated_at": "2026-04-13T00:00:00Z"
     }
   }
 }