refactor(marketplace): split cc-architect from ultraplan-local into its own plugin

Extract `/ultra-cc-architect-local` and `/ultra-skill-author-local` plus all 7
supporting agents, the `cc-architect-catalog` skill (13 files), the
`ngram-overlap.mjs` IP-hygiene script, and the skill-factory test fixtures
from `ultraplan-local` v2.4.0 into a new `ultra-cc-architect` plugin v0.1.0.

Why: ultraplan-local had drifted into containing two distinct domains — a
universal planning pipeline (brief → research → plan → execute) and a
Claude-Code-specific architecture phase. Keeping them together forced users
to inherit an unfinished CC-feature catalog (~11 seeds) when they only
wanted the planning pipeline, and locked the catalog and the pipeline into
the same release cadence. The architect was already optional and decoupled
at the code level — only one filesystem touchpoint remained
(auto-discovery of `architecture/overview.md`), which already handles
absence gracefully.

Plugin manifests:
- ultraplan-local: 2.4.0 → 3.0.0 (description + keywords updated)
- ultra-cc-architect: new at 0.1.0 (pre-release; catalog is thin, Fase 2/3
  of skill-factory unbuilt, decision-layer empty, fallback list still
  needed)

What stays in ultraplan-local: brief/research/plan/execute commands, all
19 planning agents, security hooks, plan auto-discovery of
`architecture/overview.md` (filesystem-level contract, not code-level).

What moved (28 files via git mv, R100 — full history preserved):
- 2 commands, 8 agents, 1 skill catalog (13 files), 2 scripts, 8 fixtures

Documentation updates: plugin CLAUDE.md and README.md for both plugins,
root README.md (added ultra-cc-architect section, updated ultraplan-local
section), root CLAUDE.md (added ultra-cc-architect to repo-struktur),
marketplace.json (registered ultra-cc-architect), ultraplan-local
CHANGELOG.md (v3.0.0 entry with migration guidance).

Test verification: ngram-overlap.test.mjs passes 23/23 from new location.

Memory updated: feedback_no_architect_until_v3.md now points at the new
plugin and reframes the threshold around catalog maturity rather than an
ultraplan-local milestone.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

plugins/ultraplan-local/CHANGELOG.md

@@ -4,6 +4,92 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
+## [3.0.0] - 2026-04-30
+
+### Architect extracted to its own plugin
+
+The `/ultra-cc-architect-local` and `/ultra-skill-author-local` commands, all
+seven of their agents, the `cc-architect-catalog` skill, the `ngram-overlap.mjs`
+script, and the skill-factory test fixtures moved out of `ultraplan-local` and
+into the new `ultra-cc-architect` plugin (v0.1.0).
+
+### Why
+
+`ultraplan-local` had drifted into containing two distinct domains:
+
+1. A **universal planning pipeline** (brief → research → plan → execute) that
+   is technology-agnostic and works for any implementation task.
+2. A **Claude-Code-specific architecture phase** that only makes sense when
+   building features for Claude Code itself.
+
+Keeping them in one plugin caused three problems:
+
+- Users who wanted only the planning pipeline had to clone an unfinished
+  CC-feature catalog and seven architect/skill-author agents they would
+  never invoke.
+- The architect catalog (~11 seed skills) and the planning pipeline lived on
+  different release cadences. Architect work blocked pipeline development
+  and vice-versa.
+- New users saw six commands when only four belonged to the core flow.
+
+The architect was already marked `optional, v2.2` and was fully decoupled at
+the code level — only one filesystem touchpoint remained: `/ultraplan-local`
+auto-discovers `architecture/overview.md` if present, and gracefully handles
+its absence. The split is therefore non-breaking for the planning flow.
+
+### What moved to `ultra-cc-architect`
+
+- **Commands:** `/ultra-cc-architect-local`, `/ultra-skill-author-local`
+- **Agents:** `architect-orchestrator`, `feature-matcher`, `gap-identifier`,
+  `architecture-critic`, `skill-author-orchestrator`, `concept-extractor`,
+  `skill-drafter`, `ip-hygiene-checker`
+- **Skills:** `skills/cc-architect-catalog/` (13 files)
+- **Scripts:** `scripts/ngram-overlap.mjs`, `scripts/ngram-overlap.test.mjs`
+- **Test fixtures:** `tests/fixtures/skill-factory/`,
+  `tests/fixtures/skill-drafter/`
+
+All moves used `git mv`, so history follows the files into the new plugin.
+
+### What stayed unchanged in ultraplan-local
+
+- `/ultraplan-local` Phase 1 still auto-discovers `architecture/overview.md`.
+  The discovery is filesystem-based, not plugin-based — installing both
+  plugins gives you the full pipeline (brief → research → architect → plan
+  → execute).
+- `agents/planning-orchestrator.md` retains its architecture-note
+  cross-reference.
+- All other commands (`/ultrabrief-local`, `/ultraresearch-local`,
+  `/ultraexecute-local`) are untouched.
+
+### Migration
+
+If you only used `/ultrabrief-local`, `/ultraresearch-local`,
+`/ultraplan-local`, and `/ultraexecute-local`: no action needed. Update the
+plugin and continue.
+
+If you used `/ultra-cc-architect-local` or `/ultra-skill-author-local`:
+install the new plugin alongside this one. In `~/.claude/settings.json`:
+
+```json
+{
+  "enabledPlugins": {
+    "ultraplan-local@ktg-plugin-marketplace": true,
+    "ultra-cc-architect@ktg-plugin-marketplace": true
+  }
+}
+```
+
+Custom seed skills you added to `cc-architect-catalog/` follow with the
+catalog. Use `git log --follow` if you need to track them in the new
+location.
+
+### plugin.json changes
+
+- `version`: `2.4.0` → `3.0.0`
+- `description`: now describes a four-command pipeline; CC-feature matching
+  is described as living in the separate `ultra-cc-architect` plugin
+- `keywords`: removed `cc-architecture`
+
 ## [2.4.0] - 2026-04-19
 
 ### Breaking change — background mode removed