Extract book cover utilities into BookCoverUtils

Refactors book cover and metadata handling out of Epub class into a dedicated BookCoverUtils utility. Moves FootnoteEntry struct into reader activity directory. Simplifies cache clearing to use direct storage operations instead of Epub class.

src/RecentBooksStore.cpp

@@ -1,6 +1,5 @@
 #include "RecentBooksStore.h"
 
-#include <Epub.h>
 #include <FsHelpers.h>
 #include <HalStorage.h>
 #include <JsonSettingsIO.h>
@@ -11,6 +10,8 @@
 #include <algorithm>
 #include <iterator>
 
+#include "util/BookCoverUtils.h"
+
 namespace {
 constexpr uint8_t RECENT_BOOKS_FILE_VERSION = 3;
 constexpr char RECENT_BOOKS_FILE_BIN[] = "/.crosspoint/recent.bin";
@@ -106,13 +107,12 @@ RecentBook RecentBooksStore::getDataFromBook(std::string path) const {
 
   LOG_DBG("RBS", "Loading recent book: %s", path.c_str());
 
-  // If epub, try to load the metadata for title/author and cover.
-  // Use buildIfMissing=false to avoid heavy epub loading on boot; getTitle()/getAuthor() may be
-  // blank until the book is opened, and entries with missing title are omitted from recent list.
+  // If epub, read title/author straight from the OPF (Book::open is a light
+  // container parse — no pagination, no CSS).
   if (FsHelpers::hasEpubExtension(lastBookFileName)) {
-    Epub epub(path, "/.crosspoint");
-    epub.load(false, true);
-    return RecentBook{path, epub.getTitle(), epub.getAuthor(), epub.getThumbBmpPath()};
+    std::string title, author;
+    BookCoverUtils::readMetadata(path, &title, &author);
+    return RecentBook{path, title, author, BookCoverUtils::thumbBmpPathTemplate(path)};
   } else if (FsHelpers::hasXtcExtension(lastBookFileName)) {
     // Handle XTC file
     Xtc xtc(path, "/.crosspoint");