governance: keep repository root clean; remove marker file; implement repo detection via structure heuristic; update tests and system prompts/templates

docs/devlog/DEVLOG_LLM.md

@@ -162,3 +162,12 @@ This log is concise and structured for quick machine parsing and summarization.
   - Updated proposal/plan to add architecture/module map deliverable and acceptance
 - next:
   - Add `docs/architecture.md` early in implementation per plan
+
+## 2025-09-17T16:38Z
+- context: Root cleanliness governance and marker removal
+- actions:
+  - Added clean-root rule to system prompts and AGENTS templates
+  - Removed `.codexhelper-repo`; replaced guard detection with repo-structure heuristic
+  - Updated CLI guardrail tests accordingly
+- next:
+  - Keep root minimal going forward; store assets under subdirectories

docs/wrapper.md

@@ -0,0 +1,21 @@
+# CodexHelper Wrapper — Usage and Design (Phase 1)
+
+Overview
+- CodexHelper wraps `codex`/`codex-cli` to provide modes, project scaffolding, and prompt composition.
+- Governance: TDD, zero technical debt, plan-first via Questions → Proposal → Plan, production-ready always.
+
+Status (Phase 1 in progress)
+- Implemented: `new-mode` scaffolder (repo-only), CLI skeleton, guardrails.
+- Pending (per plan): `new-project`, `run`, config precedence (YAML+yq).
+
+CLI
+- Help: `./CodexHelper --help`
+- Repo-only: `./CodexHelper new-mode --name <ModeName> [--force]`
+- Outside-repo (pending): `CodexHelper new-project --mode <ModeName> --name <project-name> --path <dir> [--force]`
+- Outside-repo (pending): `CodexHelper run [--mode <ModeName>] [--prompt-file <file>] [--config <file>] [--sandbox <mode>] [--full-auto]`
+
+Development
+- Tests: run `scripts/test.sh` (uses bats if available, falls back to internal runner).
+- Follow TDD: write failing tests first, make them pass, refactor.
+- Keep `docs/architecture.md` and README up to date as features land.
+