feat(model): author 是有序列表;Info(canonical) vs RawInfo(授权 surface) 入契约

一节课可多人署名(教研组),故 canonical author 是**有序列表**而非单值。on-disk
形式接受裸字符串(单作者)或数组(多作者),但此"字符串或数组"二态**只活在加载边界**:
RawInfo 经归一化折叠成 canonical Info,其后系统只见 List。

Lean 母本(ADR-0008 范围):新增 Model/Info.lean,把 Info(canonical,authors: List
String)与 RawInfo/RawAuthor(授权便利 surface)+ 归一化 RawInfo.toInfo 钉死——
canonical 接收端恒为列表,raw 形式不泄漏。ADR-0008 [info] 块补 author-as-list 决策。

impl 对齐:cph-model Info.author: Option<String> → authors: Vec<String>;RawAuthor
untagged enum(One|Many)+ into_vec 归一化;augmented manifest 发射 author 数组
(typst document(author:) 与模板已接受 string/array)。doc 两端互引 spec。

测试:load.rs 单作者→单元素列表;target-configs fixture 加数组作者断言多作者。
验证:lake build 绿(25 jobs);cargo test 全绿;clippy 静默;TH-141(单字符串作者)
check+build PDF 无回归。

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/cph-model/src/lib.rs

@@ -211,12 +211,23 @@ pub struct Project {
 }
 
 /// `[info]` table (passed through to render targets verbatim).
+///
+/// **Mirrors `Spec.Courseware.Info`** in the Lean semantic master
+/// (`spec/Spec/Courseware/Model/Info.lean`): the *canonical* model whose
+/// `authors` is always a list. The authoring-surface form (string-or-array
+/// `author`) is the separate [`RawInfo`] / [`RawAuthor`], normalized into this
+/// at the load boundary — mirroring the Lean `RawInfo` / `RawAuthor` split. No
+/// CI gate enforces this alignment (repo constitution); it is kept greppable.
 #[derive(Debug, Clone, PartialEq, Eq, Serialize)]
 pub struct Info {
     /// Lesson title.
     pub title: String,
-    /// Author, optional.
-    pub author: Option<String>,
+    /// Authors, in declared order. A lesson can have several (a teaching group),
+    /// so this is a list, not a single name. Empty when `[info]` declares no
+    /// `author`. The on-disk `author` accepts either a bare string (one author)
+    /// or an array of strings (see [`RawAuthor`]); both load into this `Vec`.
+    /// Mirrors Lean `Info.authors : List String`.
+    pub authors: Vec<String>,
 }
 
 /// One `[[parts]]` entry plus its loaded element descriptor.
@@ -265,10 +276,36 @@ struct RawProject {
     name: String,
 }
 
+/// The authoring-surface `[info]` (mirrors Lean `RawInfo` in
+/// `spec/Spec/Courseware/Model/Info.lean`): the raw form that exists for
+/// fill-in convenience, normalized into the canonical [`Info`] at the load
+/// boundary. Not the form the rest of the model traffics in.
 #[derive(Debug, Deserialize)]
 struct RawInfo {
     title: String,
-    author: Option<String>,
+    author: Option<RawAuthor>,
+}
+
+/// On-disk `author`: either a single name (`author = "…"`) or a list
+/// (`author = ["…", "…"]`). Mirrors Lean `RawAuthor`: a fill-in convenience whose
+/// string-or-array union lives **only** at the load boundary — [`RawAuthor::into_vec`]
+/// folds it into the canonical [`Info::authors`] `Vec`, after which it never appears.
+#[derive(Debug, Deserialize)]
+#[serde(untagged)]
+enum RawAuthor {
+    One(String),
+    Many(Vec<String>),
+}
+
+impl RawAuthor {
+    /// Flatten to the ordered author list (Lean `RawAuthor.normalize`): a single
+    /// name becomes a one-element list; a list passes through verbatim.
+    fn into_vec(self) -> Vec<String> {
+        match self {
+            RawAuthor::One(s) => vec![s],
+            RawAuthor::Many(v) => v,
+        }
+    }
 }
 
 #[derive(Debug, Deserialize)]
@@ -361,7 +398,7 @@ pub fn load(root: &Path) -> (Option<Lesson>, Vec<Diagnostic>) {
     let info = match raw.info {
         Some(i) => Info {
             title: i.title,
-            author: i.author,
+            authors: i.author.map(RawAuthor::into_vec).unwrap_or_default(),
         },
         None => {
             diags.push(

crates/cph-model/tests/fixtures/target-configs/manifest.toml

@@ -4,6 +4,8 @@ name = "target-configs"
 
 [info]
 title = "测试课：导出目标的结构化 build 配置"
+# Array form: a lesson authored by several people.
+author = ["张老师", "李老师"]
 
 # Full v2 config: explicit single-file artifact + an ordered typst-compile step.
 [targets.student]

crates/cph-model/tests/load.rs

@@ -27,7 +27,8 @@ fn valid_two_part_lesson_loads_in_order_with_no_errors() {
     assert_eq!(lesson.project.id, "fixture-valid");
     assert_eq!(lesson.project.name, "valid-2-part");
     assert_eq!(lesson.info.title, "测试课：两个部件");
-    assert_eq!(lesson.info.author.as_deref(), Some("范式教育教研组"));
+    // A single-string `author` loads as a one-element list.
+    assert_eq!(lesson.info.authors, vec!["范式教育教研组".to_string()]);
 
     // Parts preserve declared order: segment first, lemma second.
     assert_eq!(lesson.parts.len(), 2);
@@ -149,6 +150,12 @@ fn structured_target_configs_parse_into_typed_builds() {
         "well-formed target configs must have no diagnostics, got: {diags:?}"
     );
 
+    // An array `author` loads as the ordered author list.
+    assert_eq!(
+        lesson.info.authors,
+        vec!["张老师".to_string(), "李老师".to_string()]
+    );
+
     // Declared order is preserved.
     assert_eq!(lesson.target_names(), vec!["student", "archive", "teacher"]);