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-typst/src/manifest.rs

@@ -42,8 +42,15 @@ pub fn build_augmented_manifest(lesson: &Lesson) -> String {
         "title".to_string(),
         toml::Value::String(lesson.info.title.clone()),
     );
-    if let Some(author) = &lesson.info.author {
-        info.insert("author".to_string(), toml::Value::String(author.clone()));
+    if !lesson.info.authors.is_empty() {
+        let authors = lesson
+            .info
+            .authors
+            .iter()
+            .cloned()
+            .map(toml::Value::String)
+            .collect();
+        info.insert("author".to_string(), toml::Value::Array(authors));
     }
     doc.insert("info".to_string(), toml::Value::Table(info));
 

crates/cph-typst/tests/compile.rs

@@ -199,7 +199,7 @@ fn file_tree_artifact_is_deferred() {
         },
         info: Info {
             title: "t".into(),
-            author: None,
+            authors: vec![],
         },
         parts: vec![],
         targets: vec![TargetConfig {
@@ -238,7 +238,7 @@ fn shell_only_target_is_deferred() {
         },
         info: Info {
             title: "t".into(),
-            author: None,
+            authors: vec![],
         },
         parts: vec![],
         targets: vec![TargetConfig {