chore: migrate CLAUDE.md to @-import rule structure (custodian integration)

Register with state-hub under custodian domain. Replace monolithic CLAUDE.md
with thin @-import index; distribute content into .claude/rules/ per ops-bridge pattern.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/rules/architecture.md

@@ -0,0 +1,26 @@
+## Architecture
+
+kaizen-agentic has two distinct layers:
+
+### 1. Python framework (`src/kaizen_agentic/`)
+
+- **`core.py`** — `Agent` (abstract base) + `AgentConfig` (dataclass). Tracks performance, supports config updates, implements kaizen interface.
+- **`optimization.py`** — `OptimizationLoop` (runs improvement cycles, detects trends, generates recommendations) + `PerformanceMetrics` (execution time, success rate, quality scores).
+
+### 2. Agent definitions (`agents/` — 17 files)
+
+Markdown instruction sets read and followed by Claude. Not executables. Naming convention: `agent-{name}.md`.
+
+| Category | Agents |
+|----------|--------|
+| Testing | `tdd-workflow`, `test-maintenance`, `testing-efficiency` |
+| Quality | `code-refactoring`, `datamodel-optimization`, `optimization` |
+| Process | `requirements-engineering`, `keepaTodofile`, `keepaChangelog`, `keepaContributingfile`, `project-management`, `priority-evaluation` |
+| Infrastructure | `setupRepository`, `tooling-optimization` |
+| Release | `releaseManager` |
+| Docs | `claude-documentation` |
+| Support | `wisdom-encouragement` |
+
+### Custodian integration
+
+The state-hub MCP resolves the agents directory via `host_paths[hostname]` → `local_path`. Tools: `list_kaizen_agents(category?)`, `get_kaizen_agent(name)`.