docs: the 0x band is named for what it is, not for who reads it

`0x — Everyone` / `0x —— 人人都需要` describes an audience in a sentence
fragment. The style skill requires a noun phrase, and the band names are the
skeleton of the table of contents -- the place the rule matters most. It is
`0x — Fundamentals` / `0x —— 基础` now.

The paragraph that explained the bands went stale in the same place: it still
said `3x` extends the build graph, which stopped being true when the band took
in payloads, adapters and board-support packages. It is a table now, which is
also what the skill says to use for an enumeration.

The rule is extended in the skill to say it governs part and band names, not
only chapter headings, with this rename as the worked example: the audience
belongs on each chapter's "Reader" line, not in the skeleton of the contents.

Author: speak-agent

.agents/docs/2026-09-08-the-documentation-as-a-book.md

@@ -202,7 +202,7 @@ Three, each answering a question §1.1 measured as unowned.
 Bands are meaningful: the first digit is the part. Within a part the order is
 the order that part's reader needs, which is R4.
 
-### 5.1 `0x` — Everyone
+### 5.1 `0x` — Fundamentals
 
 The arc: understand the parts, get one program running, know where the examples
 are, write the manifest, add dependencies, make things optional, test.

.agents/skills/mcpp-docs-style/SKILL.md

@@ -157,10 +157,16 @@ docs/specs/    ──▶ docs/              允许
 | What decides what gets packed | What determines the package contents |
 | Consuming one | Consuming a package |
 | What you may rely on, and what changes | Stability guarantees |
+| 0x —— 人人都需要 | 0x —— 基础 |
+| 0x — Everyone | 0x — Fundamentals |
 
 「…的原因」「…的依据」「…的范围」是把 why 型标题转成名词短语的常用形。
 **保留 why 本身,去掉疑问语气。**
 
+这条同样管**部分名与段位名**,不只管章节标题。「人人都需要」描述的是受众、
+是一个句子片段;「基础」是这一段**是什么**。受众写在每章开头的「读者」那一行,
+不写在目录的骨架上。
+
 ## 五、词汇
 
 ### 不采用的类别

docs/README.md

@@ -42,13 +42,21 @@ one names it.
 
 ## Chapters
 
-The first digit is the part, so a number says where a chapter belongs: `0x` is
-what everyone needs, `1x` publishes, `2x` is toolchains and targets, `3x`
-extends the build graph, `4x` is devices and accelerators, `5x` is what a
-program may parse, `9x` is mcpp itself. Within a part the order is a reading
-order, not an alphabet.
+The first digit is the part, so a number says where a chapter belongs:
 
-### 0x — Everyone
+| | |
+|---|---|
+| `0x` | the fundamentals |
+| `1x` | publishing |
+| `2x` | toolchains and targets |
+| `3x` | extending mcpp and its ecosystem |
+| `4x` | devices and accelerators |
+| `5x` | the contracts a program may parse |
+| `9x` | mcpp itself |
+
+Within a part the order is a reading order, not an alphabet.
+
+### 0x — Fundamentals
 
 - [00 — How mcpp Works](00-how-mcpp-works.md) — the model every other chapter assumes
 - [01 — Getting Started](01-getting-started.md) — install, create, build, run

docs/zh/README.md

@@ -38,11 +38,21 @@
 
 ## 章节
 
-首位数字就是部分,所以编号本身说明一章属于哪里:`0x` 是人人都需要的,`1x` 发布,
-`2x` 工具链与目标,`3x` 扩展构建图,`4x` 设备与加速器,`5x` 是程序可以解析的东西,
-`9x` 是 mcpp 自身。同一部分内部的排列是阅读顺序,不是字母序。
+首位数字就是部分,所以编号本身说明一章属于哪里:
 
-### 0x —— 人人都需要
+| | |
+|---|---|
+| `0x` | 基础 |
+| `1x` | 发布 |
+| `2x` | 工具链与目标 |
+| `3x` | 扩展 mcpp 与它的生态 |
+| `4x` | 设备与加速器 |
+| `5x` | 程序可以解析的契约 |
+| `9x` | mcpp 自身 |
+
+同一部分内部的排列是阅读顺序,不是字母序。
+
+### 0x —— 基础
 
 - [00 —— mcpp 的运转方式](00-how-mcpp-works.md) —— 其余每章都假定的模型
 - [01 —— 快速开始](01-getting-started.md) —— 安装、创建、构建、运行