round-12: migrate P8 registries + P12 audit to AppStateStore

- app_state.py: host_state_db_path() (host-level DB, distinct from
  per-VM state_db_path); kv_get/kv_put/kv_delete on meta (namespaced
  keys; kv_put skips the no-secrets guard by design — registry docs
  hold user prompts, documented); audit_trail table (P12 record
  shape + hash chain, seq explicit); counts()/backup() gain
  audit_trail.
- swarm.py / presentation.py / browser_tasks.py: JSON-file backends
  replaced by KV rows (p8-swarm / p8-ledger / p8-browser-tasks);
  legacy JSON imported once on first load (renamed .migrated);
  corrupt row / unreadable store returns empty (fail-safe, same
  semantics as before; next successful save self-heals).
- audit_trail.py: StoreAuditTrail (same record shape, hash chain,
  filters, export as JSONL version, backed by audit_trail table);
  migrate_jsonl_to_store() moves a chain verbatim (broken chain
  refused, divergent seq refused, re-run idempotent). JSONL class
  kept for reading old files.
- P12 dict contracts now run against real P3/P5 code
  (ApprovalQueue.record -> build_approval_card ->
  card_matches_channel; CapabilityIssuer.issue -> describe ->
  PermissionRegistry.record_grant).
- P6->P3 local protocol test: real PrivsepClient + real worker
  server + real git status; worker git argv carries the real P3
  helper + useHttpPath; no token in argv/env/audit. runuser + HTTP
  pull stay real-machine-only (see gap docs).
- Gap docs updated: P8 migration done, guest-side browser follow-up
  explicitly left for the real-machine track (no task_id in the
  browser protocol yet; lifecycle needs a real VM to verify);
  P6 wiring + P12 migration marked done; production-readiness.md
  gains §20 (round-12 integration).
- Tests: new cloud/tests/test_chv_muse_round12.py, 24/24 OK;
  test_chv_muse_p8.py ledger corrupt test rewritten for the KV
  backend (+ legacy-import test). P7+P8: 95+1 tests OK.

cloud/chv/audit_trail.py

@@ -34,9 +34,13 @@ VM 内所有文件。
 - project_id 强制：``list_records()``/``export_json()`` 必须传 project_id，
   只返回该项目记录；跨项目读取返回空，不抛错（与现有
   ``list_audit`` 行为一致，不泄露“存在别的项目记录”）。
-- 持久化：先落独立 JSONL 文件（0600），待 P7 状态库就绪后迁移；
-  ``from_legacy_row()`` 把现有 ``audit_log`` 行转成统一记录
-  （标 ``legacy: true``，本身无哈希链，append 时重新入链）。
+- 持久化：round-12 已迁移到 P7 状态库（``StoreAuditTrail``，
+  宿主级 AppStateStore 的 ``audit_trail`` 表，同一记录形状与
+  哈希链）；``AuditTrail``（JSONL 0600）保留，用于读旧文件与
+  迁移源，``migrate_jsonl_to_store()`` 原样搬链（坏链拒绝、
+  分叉拒绝、重跑幂等）；``from_legacy_row()`` 把现有
+  ``audit_log`` 行转成统一记录（标 ``legacy: true``，本身无
+  哈希链，append 时重新入链）。
 """
 
 import hashlib
@@ -310,6 +314,168 @@ class AuditTrail:
             return [line.strip() for line in f if line.strip()]
 
 
+class StoreAuditTrail:
+    """AppStateStore 后端的统一审计轨迹（round-12 迁移）。
+
+    与 ``AuditTrail``（JSONL）同一记录形状、同一哈希链算法、
+    同一过滤/导出语义；持久化改走宿主级 AppStateStore 的
+    ``audit_trail`` 表（``state_dir/app-state.sqlite``）。
+    JSONL 版保留，用于读旧文件与迁移源；新写一律走本类。
+
+    写失败不静默丢（与 JSONL 版同款：append 抛错由调用方
+    决定是否 best-effort）；库打不开时 __init__ 即抛错，不
+    回空链——审计链丢了不能假装没事（与 P8 登记的 fail-safe
+    不同，见差距表）。
+    """
+
+    def __init__(self, state_dir: str) -> None:
+        if not state_dir or not isinstance(state_dir, str):
+            raise ValueError("state_dir required")
+        self.state_dir = state_dir
+        self._last_hash = GENESIS_HASH
+        self._seq = 0
+        self._load_tail()
+
+    def _open_store(self):
+        """打开宿主级状态库（每次调用新建连接，用完即关）。"""
+        from cloud.chv.app_state import AppStateStore, \
+            host_state_db_path
+        store = AppStateStore(host_state_db_path(self.state_dir))
+        store.open()
+        return store
+
+    def _load_tail(self) -> None:
+        """启动时读库尾，恢复末尾 seq 与链哈希。"""
+        with self._open_store() as store:
+            rows = store.list_audit_trail_rows()
+        if not rows:
+            return
+        last = rows[-1]
+        self._seq = int(last["seq"])
+        self._last_hash = str(last["hash"])
+
+    def append(self, project_id: str, actor: str, category: str,
+               action: str, object_type: str = "",
+               object_id: str = "", result: str = "ok",
+               reason: str = "", task_id: str = "",
+               approval_id: str = "",
+               detail: dict | None = None,
+               ts: float | None = None) -> dict:
+        """追加一条审计记录，返回该记录（含 seq 与链哈希）。"""
+        if not project_id:
+            raise ValueError("project_id 不能为空")
+        if category not in AUDIT_CATEGORIES:
+            raise ValueError("未知审计分类：%s" % category)
+        seq = self._seq + 1
+        record = {
+            "seq": seq,
+            "ts": ts if ts is not None else time.time(),
+            "project_id": project_id,
+            "actor": actor,
+            "category": category,
+            "action": action,
+            "object_type": object_type,
+            "object_id": object_id,
+            "result": result,
+            "reason": reason,
+            "task_id": task_id,
+            "approval_id": approval_id,
+            "detail": sanitize_detail(detail),
+            "prev_hash": self._last_hash,
+        }
+        chain_hash = compute_hash(self._last_hash, record)
+        record["hash"] = chain_hash
+        with self._open_store() as store:
+            store.insert_audit_trail_row(record)
+        self._seq = seq
+        self._last_hash = chain_hash
+        return dict(record)
+
+    def list_records(self, project_id: str, category: str = "",
+                     action: str = "", task_id: str = "",
+                     since: float = 0.0, until: float = 0.0,
+                     limit: int = 100, offset: int = 0) -> list:
+        """按时间倒序返回该项目的审计记录（副本，可分页过滤）。
+        project_id 为空或不匹配一律返回空列表。limit <= 0
+        表示不限制条数。"""
+        if not project_id:
+            return []
+        with self._open_store() as store:
+            rows = store.list_audit_trail_rows()
+        kept = [r for r in rows if r.get("project_id") == project_id]
+        kept = _filter_rows(kept, category, action, task_id,
+                            since, until)
+        kept.sort(key=lambda r: (r.get("ts", 0.0), r.get("seq", 0)),
+                  reverse=True)
+        if offset:
+            kept = kept[offset:]
+        if limit > 0:
+            kept = kept[:limit]
+        return [dict(r) for r in kept]
+
+    def verify(self) -> tuple[bool, int]:
+        """校验整条哈希链：返回 (是否通过, 首个坏行下标)。
+        通过时下标为 -1。"""
+        with self._open_store() as store:
+            rows = store.list_audit_trail_rows()
+        expected_prev = GENESIS_HASH
+        expected_seq = 1
+        for index, record in enumerate(rows):
+            if not _chain_ok(record, expected_prev, expected_seq):
+                return False, index
+            expected_prev = record["hash"]
+            expected_seq += 1
+        return True, -1
+
+    def export_json(self, project_id: str, dest: str) -> int:
+        """导出该项目全部审计记录为 JSON 数组，返回导出条数。"""
+        rows = self.list_records(project_id, limit=0)
+        rows.sort(key=lambda r: (r.get("ts", 0.0), r.get("seq", 0)))
+        with open(dest, "w", encoding="utf-8") as f:
+            json.dump(rows, f, ensure_ascii=False, indent=2)
+        os.chmod(dest, 0o600)
+        return len(rows)
+
+
+def migrate_jsonl_to_store(path: str, state_dir: str) -> int:
+    """把 JSONL 轨迹原样搬进 StoreAuditTrail，返回新插入条数。
+
+    先校验 JSONL 整条链（坏链即 ValueError，拒绝迁移，不静
+    默丢行）；行按原文 seq/hash/prev_hash 插入，不重算链；
+    库里已有且内容相同的 seq 跳过（幂等，可重跑）；已有但
+    内容不同的 seq 即 ValueError（分叉，fail-closed）。
+    文件不存在回 0。"""
+    if not os.path.exists(path):
+        return 0
+    trail = AuditTrail(path)
+    ok, bad = trail.verify()
+    if not ok:
+        raise ValueError("JSONL 审计链校验失败，拒绝迁移：行 %d"
+                         % bad)
+    rows = trail._read_all()
+    from cloud.chv.app_state import AppStateStore, \
+        host_state_db_path
+    store = AppStateStore(host_state_db_path(state_dir))
+    store.open()
+    try:
+        existing = {int(r["seq"]): r
+                    for r in store.list_audit_trail_rows()}
+        inserted = 0
+        for row in sorted(rows, key=lambda r: int(r.get("seq", 0))):
+            seq = int(row["seq"])
+            if seq in existing:
+                if existing[seq] != row:
+                    raise ValueError(
+                        "审计 seq %d 在库里已有不同内容，拒绝迁移"
+                        % seq)
+                continue
+            store.insert_audit_trail_row(row)
+            inserted += 1
+        return inserted
+    finally:
+        store.close()
+
+
 def _filter_rows(rows: list, category: str, action: str,
                 task_id: str, since: float, until: float) -> list:
     """list() 的过滤：分类/动作/任务/时间窗口，全空即不过滤。"""