Add Branch Convention community extension to catalog and README (#2128)

Adds the spec-kit-branch-convention extension (3 commands, 1 hook) that
enables configurable branch and folder naming with built-in presets for
GitFlow, ticket-based, date-based, and custom patterns.

Addresses community request in issue #407 (39+ upvotes).

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: Quratulain-bilal

README.md

@@ -185,6 +185,7 @@ The following community-contributed extensions are available in [`catalog.commun
 | AI-Driven Engineering (AIDE) | A structured 7-step workflow for building new projects from scratch with AI assistants — from vision through implementation | `process` | Read+Write | [aide](https://github.com/mnriem/spec-kit-extensions/tree/main/aide) |
 | Archive Extension | Archive merged features into main project memory. | `docs` | Read+Write | [spec-kit-archive](https://github.com/stn1slv/spec-kit-archive) |
 | Azure DevOps Integration | Sync user stories and tasks to Azure DevOps work items using OAuth authentication | `integration` | Read+Write | [spec-kit-azure-devops](https://github.com/pragya247/spec-kit-azure-devops) |
+| Branch Convention | Configurable branch and folder naming conventions for /specify with presets and custom patterns | `process` | Read+Write | [spec-kit-branch-convention](https://github.com/Quratulain-bilal/spec-kit-branch-convention) |
 | Canon | Adds canon-driven (baseline-driven) workflows: spec-first, code-first, spec-drift. Requires Canon Core preset installation. | `process` | Read+Write | [spec-kit-canon](https://github.com/maximiliamus/spec-kit-canon/tree/master/extension) |
 | Checkpoint Extension | Commit the changes made during the middle of the implementation, so you don't end up with just one very large commit at the end | `code` | Read+Write | [spec-kit-checkpoint](https://github.com/aaronrsun/spec-kit-checkpoint) |
 | Cleanup Extension | Post-implementation quality gate that reviews changes, fixes small issues (scout rule), creates tasks for medium issues, and generates analysis for large issues | `code` | Read+Write | [spec-kit-cleanup](https://github.com/dsrednicki/spec-kit-cleanup) |

extensions/catalog.community.json

@@ -106,6 +106,38 @@
       "created_at": "2026-03-03T00:00:00Z",
       "updated_at": "2026-03-03T00:00:00Z"
     },
+    "branch-convention": {
+      "name": "Branch Convention",
+      "id": "branch-convention",
+      "description": "Configurable branch and folder naming conventions for /specify with presets and custom patterns.",
+      "author": "Quratulain-bilal",
+      "version": "1.0.0",
+      "download_url": "https://github.com/Quratulain-bilal/spec-kit-branch-convention/archive/refs/tags/v1.0.0.zip",
+      "repository": "https://github.com/Quratulain-bilal/spec-kit-branch-convention",
+      "homepage": "https://github.com/Quratulain-bilal/spec-kit-branch-convention",
+      "documentation": "https://github.com/Quratulain-bilal/spec-kit-branch-convention/blob/main/README.md",
+      "changelog": "https://github.com/Quratulain-bilal/spec-kit-branch-convention/blob/main/CHANGELOG.md",
+      "license": "MIT",
+      "requires": {
+        "speckit_version": ">=0.4.0"
+      },
+      "provides": {
+        "commands": 3,
+        "hooks": 1
+      },
+      "tags": [
+        "branch",
+        "naming",
+        "convention",
+        "gitflow",
+        "workflow"
+      ],
+      "verified": false,
+      "downloads": 0,
+      "stars": 0,
+      "created_at": "2026-04-08T00:00:00Z",
+      "updated_at": "2026-04-08T00:00:00Z"
+    },
     "canon": {
       "name": "Canon",
       "id": "canon",