injectLinksInto

Returns xhtml with a <link rel="stylesheet" .../> injected for every entry in book's Book.stylesheets list that isn't already linked, with each href made relative to pageHref (the path of the XHTML page being rendered).

For per-chapter render-time use. Unlike processBook, this is a pure string transform — no io.documentnode.epub4kmp.domain.Resource is materialized or mutated. UI layers that render one chapter at a time should prefer this over running processBook, which iterates every XHTML page in the book and defeats lazy loading.