refactor(sleep): decouple engine to top-level skillopt_sleep/ (zero research dep)

Open-source-tool / research-code separation:
  - git mv skillopt/sleep/ -> skillopt_sleep/ (top-level, sibling to the research
    skillopt/ package). History preserved as renames.
  - All imports skillopt.sleep.* -> skillopt_sleep.*.
  - Vendor the validation gate into skillopt_sleep/gate.py (a self-contained copy
    of skillopt.evaluation.gate). The engine now has ZERO dependency on the
    research package — verified: grep finds no `from skillopt.` in skillopt_sleep/,
    and consolidate's gate resolves to skillopt_sleep.gate.
  - Plugin scripts/commands/skill call `-m skillopt_sleep`.

29 tests pass; `python -m skillopt_sleep` runs standalone.

Co-Authored-By: Claude Opus 4 <noreply@anthropic.com>

skillopt_sleep/staging.py

@@ -0,0 +1,103 @@
+"""SkillOpt-Sleep — Stage 5/6: staging and adoption.
+
+Implements the Dreams safety contract: the cycle never mutates the user's
+live CLAUDE.md / SKILL.md. It writes proposals + a human-readable report into
+a staging directory; a separate, explicit `adopt` step copies them over the
+live files after taking a backup.
+"""
+from __future__ import annotations
+
+import json
+import os
+import shutil
+import time
+from typing import List, Optional
+
+from skillopt_sleep.types import SleepReport
+
+
+def _ts_dir() -> str:
+    return time.strftime("%Y%m%d-%H%M%S", time.localtime())
+
+
+def staging_root(project: str) -> str:
+    return os.path.join(project, ".skillopt-sleep", "staging")
+
+
+def latest_staging(project: str) -> Optional[str]:
+    root = staging_root(project)
+    if not os.path.isdir(root):
+        return None
+    subs = sorted(
+        (os.path.join(root, d) for d in os.listdir(root)),
+        key=lambda p: os.path.getmtime(p),
+        reverse=True,
+    )
+    return subs[0] if subs else None
+
+
+def write_staging(
+    project: str,
+    *,
+    report: SleepReport,
+    proposed_skill: Optional[str],
+    proposed_memory: Optional[str],
+    live_skill_path: str,
+    live_memory_path: str,
+    report_md: str,
+) -> str:
+    """Write proposals + report into staging/<ts>/ and return that path."""
+    out = os.path.join(staging_root(project), _ts_dir())
+    os.makedirs(out, exist_ok=True)
+
+    manifest = {
+        "live_skill_path": live_skill_path,
+        "live_memory_path": live_memory_path,
+        "has_skill": proposed_skill is not None,
+        "has_memory": proposed_memory is not None,
+        "accepted": report.accepted,
+    }
+    if proposed_skill is not None:
+        with open(os.path.join(out, "proposed_SKILL.md"), "w", encoding="utf-8") as f:
+            f.write(proposed_skill)
+    if proposed_memory is not None:
+        with open(os.path.join(out, "proposed_CLAUDE.md"), "w", encoding="utf-8") as f:
+            f.write(proposed_memory)
+    with open(os.path.join(out, "report.json"), "w", encoding="utf-8") as f:
+        json.dump(report.to_dict(), f, ensure_ascii=False, indent=2)
+    with open(os.path.join(out, "report.md"), "w", encoding="utf-8") as f:
+        f.write(report_md)
+    with open(os.path.join(out, "manifest.json"), "w", encoding="utf-8") as f:
+        json.dump(manifest, f, ensure_ascii=False, indent=2)
+    return out
+
+
+def _backup(path: str, backup_dir: str) -> None:
+    if os.path.exists(path):
+        os.makedirs(backup_dir, exist_ok=True)
+        shutil.copy2(path, os.path.join(backup_dir, os.path.basename(path)))
+
+
+def adopt(staging_dir: str) -> List[str]:
+    """Copy staged proposals over the live files, backing up first.
+
+    Returns the list of live paths that were updated.
+    """
+    with open(os.path.join(staging_dir, "manifest.json")) as f:
+        manifest = json.load(f)
+    backup_dir = os.path.join(staging_dir, "backup")
+    updated: List[str] = []
+
+    if manifest.get("has_skill"):
+        live = manifest["live_skill_path"]
+        os.makedirs(os.path.dirname(live), exist_ok=True)
+        _backup(live, backup_dir)
+        shutil.copy2(os.path.join(staging_dir, "proposed_SKILL.md"), live)
+        updated.append(live)
+    if manifest.get("has_memory"):
+        live = manifest["live_memory_path"]
+        os.makedirs(os.path.dirname(live), exist_ok=True)
+        _backup(live, backup_dir)
+        shutil.copy2(os.path.join(staging_dir, "proposed_CLAUDE.md"), live)
+        updated.append(live)
+    return updated