fix(rebase): migrate the replayed E2B branch onto the rebased parent

The linear replay carried old-lineage content over parent-owned files;
this checkpoint restores them and adapts the branch to the parent's
post-rebase seam:

- restore all pty/lsp/subprocess/code-runtime surfaces to the parent's
  exact content (this branch claims none of them) and drop the net-zero
  code-runtime-e2b/pty-e2b/lsp-e2b residue and its registrations
- widen serializeRemoteEnvironment to the seam's NodeJS.ProcessEnv
  tombstone contract: an explicit undefined removes an ambient entry
- migrate the two E2B fixture Agent stubs to the Inbox-model interface
  and Session.create
- re-apply the branch's gen-doc-graphs roles, THIRD_PARTY_NOTICES e2b
  row, and packages/README group row (trimmed to the doc budget);
  regenerate catalogs and re-record bilingual pairings

docs/architecture.zh.md

@@ -25,7 +25,6 @@
 |---|---|---|
 | `ctx.llm` | [`llm/`](../packages/llm/README.md) | 适配器注册表和模型流式调用 |
 | `ctx.tokenMeter` | [`llm/token-meter`](../packages/llm/token-meter/README.md) | 感知回放的单实例请求压力与表面压力 |
-| `ctx.e2b` | [`e2b/`](../packages/e2b/README.md) | 共享 E2B 沙箱 |
 | `ctx.bash` | [`bash/`](../packages/bash/README.md) | 前台和后台命令执行 |
 | `ctx.subprocess` | [`subprocess/`](../packages/subprocess/README.md) | 可执行文件查找、受管进程树、终端 |
 | `ctx.pty` | [`pty/`](../packages/pty/README.md) | 按 owner 隔离的持久化终端会话 |