docs(code-runtime-python): correct the claims the new backend invalidated

Adding a published Python backend and reordering `flush_line` left several
owning documents stating things that are no longer true.

`src/invariant.ts` justified its empty installer with "ships only the fd-3
wire-protocol codec", which the subprocess execution path contradicts. The
reason now states the actual one: every relation this backend maintains lives
in the CPython child or on the fd-3 wire, so no same-process event sequence is
observable from a listener -- the same shape the sibling worker-thread backend
uses.

The seam's `PORTABLE_RESERVED_WORDS` and `language` JSDoc, the code-runtime
README pair, and docs/subsystems/code-runtime both said only TypeScript has a
published backend. Corrected in all four, with the generated cordis catalog
regenerated for the `language` change.

The note attributed the 12x multiple to the settlement flush holding three
copies. That stopped being true when `flush_line` was reordered to drop the
pending chunks before its push: the binding worst case is the newline path's
single near-budget write. Corrected in the note (both sides) and in the test
comment that repeated it.

The note's Testing section now registers the cases this stack added, and the
Chinese side receives the O(depth) entry it never got plus the new ones -- it
had drifted from the English.

`INTERPRETER_BASELINE_BYTES` argued 64 MiB from a RESIDENT set while RLIMIT_AS
bounds address space. It now cites the bootstrap's own measurement (30.23 MiB
of mappings for `python3 -I`), making 64 MiB roughly twice the measured
baseline.

Also: a hardcoded `(:232-235)` comment reference becomes a reference by name,
a "which now walks in O(depth) too" change narrative becomes a current-state
statement, and a stray double blank line is removed.

packages/code-runtime/code-runtime/README.zh.md

@@ -41,7 +41,7 @@ const result = await ctx.codeRuntime.run({
 
 ### 选择后端
 
-后端声明两个你可以依赖的描述符：`language`——程序必须使用的源语言，已知值为 `'typescript'` 与 `'python'`，目前只有 TypeScript 已发布——以及 `isolation`——执行基底（`'worker-thread'`、`'process'`、`'container'`），仅供部署与诊断使用，不构成安全声明。已发布的后端是 [`dsh-code-runtime-worker-thread`](../code-runtime-worker-thread/README.zh.md)，在全新的 Node Worker 线程中执行 TypeScript；[`dsh-code-runtime-python`](../code-runtime-python/README.zh.md) 持有 CPython 后端的协议格式（wire protocol）。
+后端声明两个你可以依赖的描述符：`language`——程序必须使用的源语言，已知值为 `'typescript'` 与 `'python'`，两者都有已发布的提供方——以及 `isolation`——执行基底（`'worker-thread'`、`'process'`、`'container'`），仅供部署与诊断使用，不构成安全声明。[`dsh-code-runtime-worker-thread`](../code-runtime-worker-thread/README.zh.md) 在全新的 Node Worker 线程中执行 TypeScript；[`dsh-code-runtime-python`](../code-runtime-python/README.zh.md) 在全新的 CPython 子进程中执行 Python。
 
 ### 可移植地命名绑定
 
@@ -98,7 +98,7 @@ binding-global 与 error-class 名称是语言可移植的：必须匹配标识
 
 - [PTC mode Agent Note](../../../.agents/notes/implemented/feature/2026-06-15-ptc.zh.md)——工具注册表如何消费 `ctx.codeRuntime` 并把 `run_code` 呈现给模型。
 - [Worker 线程后端](../code-runtime-worker-thread/README.zh.md)——已发布的 TypeScript 执行后端。
-- [Python 协议包](../code-runtime-python/README.zh.md)——CPython 后端的协议格式。
+- [Python 后端](../code-runtime-python/README.zh.md)——CPython 子进程执行提供方及其 fd-3 协议。
 - [代码运行时子系统参考](../../../docs/subsystems/code-runtime.zh.md)——请求／结果词汇、绑定与 `ctx.codeRuntime` 的 cordis 接口面。
 - [能力 seam](../../../.agents/notes/implemented/architecture/2026-06-13-capability-seams.zh.md)——Service Definition / Service Provider / Consumer 拆分。