fix: reuse docker boundary for production recovery

docs/BUG_HISTORY.md

@@ -3415,10 +3415,10 @@
 - 首次发现：2026-08-15
 - 最近更新：2026-08-15
 - 影响面：`Create Production Recovery Point`、生产 schema migration 前置恢复门禁，以及后续 production deploy。
-- 用户现象：`main` 与 `staging` 已同步且 release gate 成功，但生产恢复 workflow Run 1865 在创建备份前失败，日志为 `/opt/jyotisha-production/.state/mutation.lock: Permission denied`；迁移和部署因此保持阻断，生产运行版本未改变。
-- 根因：生产 bootstrap 遗留的 `.state` 路径或既有 lock 仍为非 `deploy` 所有。原恢复脚本只执行 `install -d -m 700`；对已经存在的目录该命令不会恢复所有权，随后由 `deploy` 打开共享锁即被内核拒绝。失败发生在 `pg_dump` 前，因此本轮没有生成可用恢复证明，也没有执行 schema migration。
-- 修复：恢复脚本先对 `.state`、`backups` 和既有 `mutation.lock` 做类型与非符号链接校验，再通过已审查的部署树 sudo 边界仅恢复这些路径到当前 `deploy` UID/GID 和私有权限；不递归改动备份文件、不删除或替换 lock inode，随后仍用同一个 `flock -n` fail-closed 获取共享 host lock。同步更新生产 runbook 和静态安全契约测试。
+- 用户现象：`main` 与 `staging` 已同步且 release gate 成功，但生产恢复 workflow Run 1865 在创建备份前失败，日志为 `/opt/jyotisha-production/.state/mutation.lock: Permission denied`。首次修复后的 Run 1869 仍在 `pg_dump` 前失败，准确日志为 `sudo: a password is required`；迁移和部署因此持续阻断，生产运行版本未改变。
+- 根因：生产 bootstrap 遗留的 `.state` 路径或既有 lock 仍为非 `deploy` 所有。原恢复脚本只执行 `install -d -m 700`；对已经存在的目录该命令不会恢复所有权，随后由 `deploy` 打开共享锁即被内核拒绝。首次修复又错误假设主机已为 `deploy` 配置独立的免密 `chown`，但真实生产 sudo 边界只允许已审查的 Docker 命令，因此 `sudo -n chown` 立即失败。两次失败都发生在 `pg_dump` 前，没有生成可用恢复证明，也没有执行 schema migration。
+- 修复：恢复脚本先对 `.state`、`backups` 和既有 `mutation.lock` 做类型与非符号链接校验，取得当前运行 PostgreSQL 容器的不可变本地 image ID，再复用既有 `sudo -n docker` 边界启动一次性所有权修复容器：`--pull never`、无网络、只读根文件系统、`no-new-privileges`、删除全部 capability 后只保留 `CHOWN`，并且仅绑定 `.state` 与 `backups`。helper 只恢复两个目录 mount point 和既有普通 lock 到当前 `deploy` UID/GID；不递归改动历史备份、不删除或替换 lock inode，随后仍用同一个 `flock -n` fail-closed 获取共享 host lock。同步更新生产 runbook 和静态安全契约测试，明确不得再扩大主机 sudoers。
 - 验证：本地 `bash -n`、YAML parse、聚焦 workflow contract 与 `git diff --check` 必须通过；远端必须重新完成 staging quality/deploy、exact-SHA release gate、真实 production dump + disposable restore + off-site artifact，再允许 migration/deploy。
 - 防复发：生产私有状态目录必须保持 `deploy:deploy 0700`，共享 lock 必须是普通非 symlink 文件且不可通过删除重建来“修复”；任何恢复流程失败都不得手填 `restore_verified=true` 或跳过恢复门禁。
-- 相关记录：生产迁移 runbook、Run 1865
+- 相关记录：生产迁移 runbook、Run 1865、Run 1869
 - 修复版本：待提交（精确 SHA 以重新发布后的远端分支与 production health 为准）

docs/operations/production-server-migration-2026-08.md

@@ -60,7 +60,7 @@ Do not put the Ubuntu password, database URLs, Resend key, payment key, model-pr
 Perform this interactively before any workflow dispatch:
 
 1. Patch Ubuntu and install Docker Engine, Compose v2, `rsync`, `curl`, `jq`, `flock`, and UFW.
-2. Create a non-root `deploy` user, install a dedicated Ed25519 public key, and grant only the reviewed passwordless commands needed for Docker and deployment-tree ownership.
+2. Create a non-root `deploy` user, install a dedicated Ed25519 public key, and grant only the reviewed passwordless Docker command used by the deployment workflows. Ownership normalization must reuse the capability-constrained helper container described below rather than adding a separate passwordless host `chown` rule.
 3. Verify a second key-only session and rotate the exposed bootstrap password. For this host, the production owner explicitly requires password authentication to remain enabled for other operators; do not change `PasswordAuthentication`. Workflows must still use the dedicated deploy key.
 4. Permit only the confirmed SSH port plus `80/tcp`, `443/tcp`, and `443/udp`. Do not publish `3000`, `5200`, `5432`, or the Docker API.
 5. Create a 2–4 GB swap file and enable Docker log rotation. Keep at least 15 GB free before the first image pull and database import.
@@ -90,7 +90,7 @@ Use distinct production credentials for PostgreSQL roles, Better Auth, Resend, b
 
 ## Database migration engineering gate
 
-Before importing data, dispatch Gitea Actions → `Create Production Recovery Point` for the exact accepted release SHA. It validates the private production `.state` and `backups` paths, restores only their documented `deploy` ownership and an existing regular shared lock when bootstrap ownership has drifted, creates an AES-256-CBC/PBKDF2 encrypted custom-format dump on the production host, restores it into a disposable database, verifies non-sensitive table counts, removes only the disposable database, and uploads the encrypted dump plus verification manifest as a 30-day Gitea Actions artifact. It must preserve the existing lock inode and fail closed on symlinks or non-regular lock paths. The workflow prints the non-sensitive `recovery_reference` and exact UTC `recovery_created_at`; use those values only after the artifact upload succeeds.
+Before importing data, dispatch Gitea Actions → `Create Production Recovery Point` for the exact accepted release SHA. It validates the private production `.state` and `backups` paths, obtains the immutable image ID of the already-running PostgreSQL container, and reuses the existing passwordless Docker boundary to run that local image with `--pull never`, no network, a read-only root filesystem, `no-new-privileges`, and only `CHOWN` retained. With only `.state` and `backups` bind-mounted, it restores the two directory mount points and an existing regular shared lock to documented `deploy` ownership when bootstrap ownership has drifted. It then creates an AES-256-CBC/PBKDF2 encrypted custom-format dump on the production host, restores it into a disposable database, verifies non-sensitive table counts, removes only that disposable database, and uploads the encrypted dump plus verification manifest as a 30-day Gitea Actions artifact. It must preserve the existing lock inode, avoid recursively changing historical backups, and fail closed on symlinks, non-regular lock paths, or an unexpected image identity. The workflow prints the non-sensitive `recovery_reference` and exact UTC `recovery_created_at`; use those values only after the artifact upload succeeds.
 
 Then dispatch Gitea Actions → `Migrate Production Database` for the same exact accepted release SHA. The workflow requires `main == staging == deploy_sha`, the same successful staging backend gate, the same manual release gate, and the public staging `/api/health` identity for that SHA. It also requires the recovery workflow's non-sensitive reference, exact UTC creation time, and `restore_verified=true`; the recovery point must be no more than 24 hours old and must already have passed the restore verification. It verifies the current production revision, obtains the gate-attested immutable Web image, runs the schema checker, applies only pending application schema migrations, and requires the checker to converge afterward.