Theorem v1.1.0

Added

• Book export — Right-click a book (or select several and use the batch
  Export action) to copy the original file out of the app:
  • Desktop: native save dialog via @tauri-apps/plugin-dialog + writeFile.
  • Android: a new save_file_mobile command writes to the system Downloads
    folder (Download/Theorem) through the mobile-folder-scan plugin's
    MediaStore saveFile method.
  • Browser/web: <a download> fallback when Tauri is unavailable.
  • Books synced from another device are fetched on demand from a paired peer
    first, with a clear message when none is available.
  • Results surface as a toast notification (sonner) instead of an alert.
• Edit Book Info — A full metadata editor that replaces the old
  title-only rename. Access it from the book's context menu ("Edit Info") or
  the new Edit button in Book Info. Editable fields: title, author,
  description, publisher, published date, language, ISBN, category, tags, and
  rating.
• Cover editing — Change or remove a book's cover from the same Edit modal
  via device image picker or a fetch-from-URL field, with an instant preview.
  Changes are written into EPUB files as well as the library (see below).
• EPUB metadata/cover write-back — New rewrite_epub_metadata Rust
  command updates the OPF <metadata> dc: fields and replaces or embeds the
  cover image (manifest + cover meta updated) directly in the stored .book
  file. Encrypted EPUBs are rejected; the browser gets a best-effort fflate
  fallback (epub-write-browser.ts) that keeps the mimetype entry stored
  uncompressed. Edits are saved in-app even when file write-back fails (e.g.
  a synced book not yet downloaded).
• Back to previous reading location — Clicking a citation or footnote and
  the mobile back gesture/hardware back now returns you to the page you were
  on before following the link:
  • Browser back gesture and Android hardware back step through foliate's
    built-in location history (panels/color picker are closed first).
  • Desktop shortcut Alt+Left / Alt+Right (previous/next location).
  • EPUB only; PDF has no location history and is unaffected.
• Workbench remembers your last card — The card view (and the active
  filter, sort, and list/cards toggle) is remembered per session in
  sessionStorage (theorem-workbench:view-state). Navigate away and back
  and you land on the exact card you were reading, resolved by annotation id
  so resorting or filtering doesn't lose your place.

Fixed

• Edit Book Info modal could not scroll — The modal's <form> wrapper
  broke the flex layout, so the body never shrank and the footer (Save
  button) was clipped below the 90vh viewport limit on smaller screens. The
  form is now a flex column so ModalBody scrolls and Save stays visible.
• Rust unit tests for EPUB parsing — Two epub_parser fixtures used a
  truncated <package xmlns="http:..."> namespace URI (introduced by an
  overly aggressive comment-strip pass), which made test_locate_toc_sources
  and test_read_epub_metadata_full fail. The fixture tag was repaired; the
  full Rust test suite is green again.