feat(storage): import immutable dependency snapshots

[zhiiw]

Summary

• import an explicitly selected, already-provisioned npm node_modules tree into fresh Maka-owned inodes
• bind the logical package/lock/Node identity to the exact dependency content digest and a durable receipt
• expose only the narrow snapshot authority and opaque read-only lease; keep generic producers and receipt writers private
• converge after process exit both after artifact publication and after receipt durability

Primary invariant

An existing dependency tree may receive a managed read-only lease only when the bounded source observation, the Maka-owned copy, and the durable receipt all identify the exact same bytes. This slice never starts npm, accesses the network, reads PATH, or publishes source-owned inodes.

Owner and atomic boundary

ManagedDependencySnapshotAuthority owns source observation and source-to-staging copy. The existing storage-root authority exclusively owns artifact publication, receipt commit, lease lifetime, cross-process exclusion, and GC.

The filesystem and SQLite are not presented as one transaction: an artifact without a receipt is removed and rebuilt; a durable matching receipt is reopened and revalidated; any artifact/receipt/content mismatch fails closed.

Verification

• storage build: passed
• focused dependency suites: 30 tests, 28 passed, 2 platform-conditional POSIX skips, 0 failed
• real child-process crash/reopen after artifact publication: passed
• real child-process crash/reopen after receipt durability: passed
• Biome and git diff --check: passed

This remains a stacked Draft. Its base is the packaged managed-coding-v2 crash gate; the next slice binds this opaque lease into T1 before a sandbox may consume it.

中文说明

摘要

• 将用户明确选择、已经存在的 npm node_modules 导入到全新的 Maka-owned inode；
• 把 package/lock/Node 逻辑身份与依赖树的 exact content digest、durable receipt 绑定；
• 只导出窄化的 snapshot authority 和 opaque read-only lease，generic producer 与 receipt writer 保持私有；
• 覆盖 artifact 发布后、receipt 持久化后两处真实进程退出并重启收敛。

主要不变量

只有当有界 source observation、Maka-owned copy 和 durable receipt 都指向完全相同的依赖字节时，现有依赖树才能获得 managed read-only lease。本切片不会启动 npm、访问网络、读取 PATH，也不会直接发布 source inode。

Owner 与原子边界

ManagedDependencySnapshotAuthority 只拥有 source observation 与 source-to-staging copy。底层 storage-root authority 唯一拥有 artifact publication、receipt commit、lease lifecycle、跨进程互斥和 GC。

文件系统与 SQLite 不伪装成单事务：有 artifact 无 receipt 时删除并重建；receipt 已持久化且匹配时重开并重验；artifact、receipt 或内容任一不一致都 fail closed。

当前仍为 stacked Draft。下一切片会先在 T1 中绑定 opaque dependency lease，再允许 sandbox 消费，缺失时不回退 checkout node_modules。