Add Improve Extension to community catalog (#2997)

Add improve extension submitted by @d0whc3r to:
- extensions/catalog.community.json (alphabetical order)
- docs/community/extensions.md community extensions table

Closes #2972

Co-authored-by: Manfred Riem <mnriem@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

docs/community/extensions.md

@@ -55,6 +55,7 @@ The following community-contributed extensions are available in [`catalog.commun
 | Fleet Orchestrator | Orchestrate a full feature lifecycle with human-in-the-loop gates across all SpecKit phases | `process` | Read+Write | [spec-kit-fleet](https://github.com/sharathsatish/spec-kit-fleet) |
 | GitHub Issues Integration 1 | Generate spec artifacts from GitHub Issues - import issues, sync updates, and maintain bidirectional traceability | `integration` | Read+Write | [spec-kit-github-issues](https://github.com/Fatima367/spec-kit-github-issues) |
 | GitHub Issues Integration 2 | Creates and syncs local specs from an existing GitHub issue | `integration` | Read+Write | [spec-kit-issue](https://github.com/aaronrsun/spec-kit-issue) |
+| Improve Extension | Audits any codebase as a senior advisor and writes prioritized, self-contained spec prompts under specs/ that the spec-kit lifecycle can process | `process` | Read+Write | [spec-kit-improve](https://github.com/d0whc3r/spec-kit-improve) |
 | Interactive HTML Preview | Generate self-contained interactive HTML prototypes from Spec Kit artifacts | `docs` | Read+Write | [spec-kit-preview](https://github.com/bigsmartben/spec-kit-preview) |
 | Intelligent Agent Orchestrator | Cross-catalog agent discovery and intelligent prompt-to-command routing | `process` | Read+Write | [spec-kit-orchestrator](https://github.com/pragya247/spec-kit-orchestrator) |
 | Iterate | Iterate on spec documents with a two-phase define-and-apply workflow — refine specs mid-implementation and go straight back to building | `docs` | Read+Write | [spec-kit-iterate](https://github.com/imviancagrace/spec-kit-iterate) |

extensions/catalog.community.json

@@ -1295,6 +1295,49 @@
       "created_at": "2026-06-12T00:00:00Z",
       "updated_at": "2026-06-12T00:00:00Z"
     },
+    "improve": {
+      "name": "Improve Extension",
+      "id": "improve",
+      "description": "Audits any codebase as a senior advisor and writes prioritized, self-contained spec prompts under specs/ that the spec-kit lifecycle can process.",
+      "author": "d0whc3r",
+      "version": "1.0.1",
+      "download_url": "https://github.com/d0whc3r/spec-kit-improve/releases/download/v1.0.1/improve-1.0.1.zip",
+      "repository": "https://github.com/d0whc3r/spec-kit-improve",
+      "homepage": "https://d0whc3r.github.io/spec-kit-improve/",
+      "documentation": "https://github.com/d0whc3r/spec-kit-improve/wiki",
+      "changelog": "https://github.com/d0whc3r/spec-kit-improve/blob/main/CHANGELOG.md",
+      "license": "MIT",
+      "category": "process",
+      "effect": "read-write",
+      "requires": {
+        "speckit_version": ">=0.2.0"
+      },
+      "provides": {
+        "commands": 1,
+        "hooks": 0
+      },
+      "tags": [
+        "advisor",
+        "audit",
+        "code-quality",
+        "code-review",
+        "improvement",
+        "performance",
+        "planning",
+        "refactoring",
+        "security",
+        "spec-kit",
+        "spec-kit-extension",
+        "specs",
+        "tech-debt",
+        "testing"
+      ],
+      "verified": false,
+      "downloads": 0,
+      "stars": 0,
+      "created_at": "2026-06-16T00:00:00Z",
+      "updated_at": "2026-06-16T00:00:00Z"
+    },
     "issue": {
       "name": "GitHub Issues Integration 2",
       "id": "issue",