Add Spec Switcher extension to community catalog

Add switch extension submitted by @wagner-sousa to:
- extensions/catalog.community.json (alphabetical order)
- docs/community/extensions.md community extensions table

Closes #3932

Assisted-by: GitHub Copilot (model: claude-sonnet-4.6, autonomous)
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

docs/community/extensions.md

@@ -139,6 +139,7 @@ The following community-contributed extensions are available in [`catalog.commun
 | Spec Refine | Update specs in-place, propagate changes to plan and tasks, and diff impact across artifacts | `process` | Read+Write | [spec-kit-refine](https://github.com/Quratulain-bilal/spec-kit-refine) |
 | Spec Roadmap | Capture a durable spec roadmap after the constitution, then review specs against it before and after implementation so spec-specific decisions, outcomes, and constraints are never lost. | `process` | Read+Write | [speckit-roadmap](https://github.com/srobroek/speckit-roadmap) |
 | Spec Scope | Effort estimation and scope tracking — estimate work, detect creep, and budget time per phase | `process` | Read-only | [spec-kit-scope-](https://github.com/Quratulain-bilal/spec-kit-scope-) |
+| Spec Switcher | Navigate between specs — list available specs and switch active feature with git checkout | `process` | Read+Write | [spec-kit-switch](https://github.com/wagner-sousa/spec-kit-switch) |
 | Spec Sync | Detect and resolve drift between specs and implementation. AI-assisted resolution with human approval | `docs` | Read+Write | [spec-kit-sync](https://github.com/bgervin/spec-kit-sync) |
 | Spec Trace | Build a requirement → test traceability matrix from spec.md and the test suite — surface untested requirements and orphan tests | `code` | Read+Write | [spec-kit-trace](https://github.com/Quratulain-bilal/spec-kit-trace) |
 | Spec Validate | Comprehension validation, review gating, and approval state for spec-kit artifacts — staged quizzes, peer review SLA, and a hard gate before /speckit.implement | `process` | Read+Write | [spec-kit-spec-validate](https://github.com/aeltayeb/spec-kit-spec-validate) |

extensions/catalog.community.json

@@ -1,6 +1,6 @@
 {
   "schema_version": "1.0",
-  "updated_at": "2026-08-04T00:00:00Z",
+  "updated_at": "2026-08-07T00:00:00Z",
   "catalog_url": "https://raw.githubusercontent.com/github/spec-kit/main/extensions/catalog.community.json",
   "extensions": {
     "adrkit": {
@@ -4417,6 +4417,40 @@
       "created_at": "2026-04-22T00:00:00Z",
       "updated_at": "2026-05-30T00:00:00Z"
     },
+    "switch": {
+      "name": "Spec Switcher",
+      "id": "switch",
+      "description": "Navigate between specs — list available specs and switch active feature with git checkout",
+      "author": "Wagner Sousa",
+      "version": "1.0.0",
+      "download_url": "https://github.com/wagner-sousa/spec-kit-switch/archive/refs/tags/v1.0.0.zip",
+      "repository": "https://github.com/wagner-sousa/spec-kit-switch",
+      "homepage": "https://github.com/wagner-sousa/spec-kit-switch",
+      "documentation": "https://github.com/wagner-sousa/spec-kit-switch#readme",
+      "changelog": "https://github.com/wagner-sousa/spec-kit-switch/blob/main/CHANGELOG.md",
+      "license": "MIT",
+      "category": "process",
+      "effect": "read-write",
+      "requires": {
+        "speckit_version": ">=0.4.0"
+      },
+      "provides": {
+        "commands": 2,
+        "hooks": 0
+      },
+      "tags": [
+        "navigation",
+        "workflow",
+        "specs",
+        "sdd",
+        "git"
+      ],
+      "verified": false,
+      "downloads": 0,
+      "stars": 0,
+      "created_at": "2026-08-07T00:00:00Z",
+      "updated_at": "2026-08-07T00:00:00Z"
+    },
     "sync": {
       "name": "Spec Sync",
       "id": "sync",