feat(plugins): add OpenClaw shell for SkillOpt-Sleep

Adds a thin OpenClaw shell wrapping the SkillOpt-Sleep engine. Enables
nightly validation-gated skill improvement cycles for OpenClaw agents.

Components:
- skillopt_sleep_openclaw.py: DeepSeek V4 Pro + Ollama nomic-embed-text
  backend, mirroring the Claude/Codex/Copilot backend pattern.
- run_sleep.py: CLI entry point supporting dry-run and pre-built task files.
- run_sleep_cron.sh: bash wrapper for nightly cron invocation.
- slash_sleep.py: /sleep command (status / run / adopt / reject / cost).
- config.json: engine config tuned for our stack.
- SKILL.md: OpenClaw skill manifest.
- tests/: 14 held-out tasks across 3 categories (research-cron, devops, wiki).

OpenClaw is the 4th ecosystem in which SkillOpt-Sleep can be deployed,
joining Claude Code, Codex, and Copilot. The shell follows the same
single-engine / thin-shell pattern as the existing three plugins.

End-to-end tested: pipeline runs against real OpenClaw session transcripts,
gate correctly rejects non-improvements, staging artifacts land in
~/.skillopt-sleep/staging/<night>/. Cost: ~$0.02/night on DeepSeek V4 Pro.

plugins/openclaw/run_sleep.py

@@ -0,0 +1,122 @@
+#!/usr/bin/env python3
+"""run_sleep.py — OpenClaw entry point for SkillOpt-Sleep.
+
+Runs one nightly sleep cycle:
+  1. harvest recent session transcripts
+  2. mine recurring task patterns
+  3. replay tasks with current skill (baseline) + candidate skill (with proposed edit)
+  4. gate candidate vs baseline on held-out accuracy
+  5. stage the proposal in ~/.skillopt-sleep/staging/<night>/
+  6. leave adoption to Ethan (auto_adopt=false)
+
+Usage:
+  python3 run_sleep.py                  # one cycle, default config
+  python3 run_sleep.py --dry-run        # compute report only, no staging
+  python3 run_sleep.py --tasks path.json  # use a pre-built task file
+"""
+from __future__ import annotations
+
+import argparse
+import json
+import os
+import sys
+from pathlib import Path
+
+# Ensure the skillopt_sleep package is importable (it lives in the cloned repo)
+REPO = Path("/home/ethanclaw/.openclaw/workspace/SkillOpt")
+sys.path.insert(0, str(REPO))
+
+# Register our backend before importing cycle
+from skillopt_sleep_openclaw import OpenClawDeepSeekBackend
+import skillopt_sleep.backend as _b
+_b._BACKENDS = getattr(_b, "_BACKENDS", {})
+_b._BACKENDS["openclaw-deepseek"] = OpenClawDeepSeekBackend
+
+# Patch get_backend to know about our backend
+_orig_get_backend = _b.get_backend
+
+def get_backend(name, model="", codex_path=""):
+    if name == "openclaw-deepseek":
+        return OpenClawDeepSeekBackend(model=model or "deepseek-v4-pro")
+    return _orig_get_backend(name, model=model, codex_path=codex_path)
+
+_b.get_backend = get_backend
+
+from skillopt_sleep.cycle import run_sleep_cycle
+from skillopt_sleep.config import load_config
+
+
+def main() -> int:
+    ap = argparse.ArgumentParser(description="OpenClaw SkillOpt-Sleep nightly cycle")
+    ap.add_argument("--dry-run", action="store_true", help="Compute but don't stage")
+    ap.add_argument("--config", default="/home/ethanclaw/.openclaw/workspace/skills/skillopt-sleep/config.json")
+    ap.add_argument("--tasks", default=None, help="Path to pre-built tasks JSON")
+    ap.add_argument("--verbose", action="store_true")
+    args = ap.parse_args()
+
+    # Load config from file then override with our defaults
+    overrides = {}
+    if os.path.exists(args.config):
+        with open(args.config) as f:
+            overrides.update(json.load(f))
+    overrides.pop("_comment", None)
+
+    cfg = load_config(**overrides)
+
+    seed_tasks = None
+    if args.tasks:
+        from skillopt_sleep.types import TaskRecord
+        with open(args.tasks) as f:
+            raw = json.load(f)
+        # Translate our test-set fields → TaskRecord fields
+        seed_tasks = []
+        for t in raw:
+            seed_tasks.append(TaskRecord(
+                id=t['id'],
+                project=t.get('project', 'openclaw'),
+                intent=t.get('intent') or t.get('prompt', ''),
+                context_excerpt=t.get('context_excerpt', ''),
+                attempted_solution=t.get('attempted_solution', ''),
+                outcome=t.get('outcome', 'unknown'),
+                reference_kind=t.get('reference_kind', 'rubric'),
+                reference=t.get('reference', ''),
+                judge=t.get('judge', {}),
+                tags=t.get('tags', []),
+                source_sessions=t.get('source_sessions', []),
+                split=t.get('split', 'train'),
+            ))
+
+    print(f"[skillopt-sleep] starting cycle...")
+    print(f"  backend: {cfg.get('backend')}")
+    print(f"  project: {cfg.get('invoked_project')}")
+    print(f"  max tasks: {cfg.get('max_tasks_per_night')}")
+    print(f"  edit budget: {cfg.get('edit_budget')}")
+    print(f"  dry_run: {args.dry_run}")
+
+    outcome = run_sleep_cycle(cfg, seed_tasks=seed_tasks, dry_run=args.dry_run)
+
+    r = outcome.report
+    print(f"\n=== Report — night {r.night} ===")
+    print(f"  sessions harvested: {r.n_sessions}")
+    print(f"  tasks mined: {r.n_tasks}  (replayed: {r.n_replayed})")
+    print(f"  baseline: {r.baseline_score:.3f}  ->  candidate: {r.candidate_score:.3f}")
+    print(f"  gate: {r.gate_action}  accepted={r.accepted}")
+    print(f"  tokens: {r.tokens_used}")
+    if r.edits:
+        print(f"  applied edits ({len(r.edits)}):")
+        for e in r.edits:
+            print(f"    [{e.target}/{e.op}] {e.content[:80]}...")
+    if r.rejected_edits:
+        print(f"  rejected edits ({len(r.rejected_edits)}) — kept as negative feedback")
+    if r.notes:
+        for n in r.notes:
+            print(f"  note: {n}")
+    if outcome.staging_dir:
+        print(f"\n  STAGED at: {outcome.staging_dir}")
+        print(f"  Review with: ls {outcome.staging_dir}")
+
+    return 0 if r.accepted or r.candidate_score >= r.baseline_score else 1
+
+
+if __name__ == "__main__":
+    sys.exit(main())