Reflowable ebooks (EPUBs) don't have inherent page numbers since layout
depends on device settings. Add an EstimatedPages() function that converts
total character count to an estimated print page count using the industry
standard of 1800 characters per page.
This provides a consistent, device-independent page count for progress
display (e.g., "Page 89 of 196" for a reflowable EPUB), matching how
KOReader and similar readers handle the same problem.
Fix incorrect struct tags for Page, TotalPages, and PageY fields.
Previously used 'int' tag instead of proper JSON field names,
which would cause serialization issues.
- Add internal/sync package with format detection
- FormatGroup types: reflowable, fixed_layout, comic_archive
- DetectFormatGroup() function based on mimetype and file extension
- MimeType mappings for common ebook formats
- Progress conversion engine with:
- ConvertProgress() between format groups
- Extract percentage from various progress formats
- PageToPercentage / PercentageToPage helpers
- CharacterToPercentage / PercentageToCharacter helpers
- MergeProgress() with 'max progress wins' strategy
- FormatProgressForDisplay() for UI rendering
- Add sqlc queries for format detection and progress updates
- BulkUpdateFormatGroups query for auto-format detection
- GetUniversalProgress query with all location references
- UpdateUniversalProgress query with device sync metadata
- ReadingHistory queries for session tracking
john-okeefe