Port PR #838 (epub cover fallback logic) and PR #907 (cover outlines): - Add fallback cover filename probing when EPUB metadata lacks cover info - Case-insensitive extension checking for cover images - Detect and re-generate corrupt/empty thumbnail BMPs - Always draw outline rect on cover tiles for legibility (PR #907) - Upgrade Storage.exists() checks to Epub::isValidThumbnailBmp() - Fallback chain: Real Cover → PlaceholderCoverGenerator → X-pattern marker - Add epub.load retry logic (cache-only first, then full build) - Adapt upstream Serial.printf calls to LOG_DBG/LOG_ERR macros Co-authored-by: Cursor <cursoragent@cursor.com>
3.7 KiB
3.7 KiB