Theorem v1.2.1

Added

• Discover Editorial Storefront & 75,000+ Global Catalog Search (#59) —
  Browse and download books directly into your Theorem library with 1-click import.
  Features curated editorial sections (Timeless Essentials, Restored Editions via
  Standard Ebooks, Philosophy & Thought, Classic Fiction), live debounced global
  search across 75,000+ public domain classics, @tanstack/react-virtual DOM
  virtualization, and support for custom self-hosted OPDS 1.2 feeds (Calibre, Kavita,
  Komga).
• Theorem Clothbound Cover Engine — Deterministic typography and 7 refined
  clothbound bookcloth color palettes (crimson, obsidian, navy, forest,
  ochre, slate, plum) with double hairline rules for books missing bundled
  artwork.
• In-Place Footnote & Citation Popovers — Tapping footnotes, citations, and
  noteref links now reveals a non-disruptive, elegant popover overlay with rendered
  HTML, copy action, and an optional jump button, without losing your reading location.
• Native Brand Splash Screen — Instant 0ms first-frame splash screen featuring
  the Theorem Q.E.D. emblem directly rendered by the webview on boot, seamlessly
  fading out once storage hydration completes.

Fixed & Performance

• Adaptive SQLite Memory & Pool Optimization (#58) — Configured platform-aware
  database pools and memory limits (2 connections and 32MB mmap on Android; 4 connections
  and 256MB mmap on Desktop) along with an automatic background visibilitychange
  listener executing PRAGMA shrink_memory; when Theorem is minimized or tabbed away.
• Mobile Navigation & Hardware Back Button — Resolved Android back button
  history stack desynchronization by removing synthetic sentinels, implementing
  clean LIFO state preservation in src/App.tsx, and adding automatic back-button
  dismissal to all modals and dialogs.
• Reader Titlebar Status & Progress — Placed a dedicated reading progress and
  chapter indicator centered in desktop titlebars, and ensured page/chapter status
  is always clearly visible on mobile screens.
• PDF.js GPU Memory Deallocation — Reset canvas dimensions (width = 1, height = 1)
  and released ImageBitmap references on page unmount to eliminate GPU backing store
  retention during rapid scrolling.
• Mobile Performance & IPC Optimization — Completely eliminated mobile lag and
  UI stutter on Android by configuring tauri_plugin_log to use Stdout only,
  preventing hundreds of background IPC log events from flooding the Android JNI
  bridge and starving the JavaScript thread.
• Reader Re-render Elimination — Memoized reader history callbacks and decoupled
  render hooks in ReaderViewport to prevent infinite re-render loops on page turns.