Add book support for DOI

Fixes #1714

Author: dragonstyle

src/project/types/book/book-render.ts

@@ -21,6 +21,7 @@ import {
   kAuthor,
   kDate,
   kDescription,
+  kDoi,
   kNumberSections,
   kOutputExt,
   kOutputFile,
@@ -646,6 +647,7 @@ function withBookTitleMetadata(format: Format, config?: ProjectConfig): Format {
     setMetadata(kDateFormat);
     setMetadata(kAbstract);
     setMetadata(kDescription);
+    setMetadata(kDoi);
   }
   return format;
 }

src/project/types/book/book-shared.ts

@@ -23,6 +23,7 @@ export type BookConfigKey =
   | "downloads"
   | "tools"
   | "title"
+  | "doi"
   | "subtitle"
   | "author"
   | "description"