This commit completes a series of fixes addressing dictionary crashes,
memory issues, and UI/UX improvements.
Memory & Stability (from previous checkpoints):
- Add uncompressed dictionary (.dict) support to avoid decompression
memory issues with large dictzip chunks (58KB -> direct read)
- Implement chunked on-demand HTML parsing for large definitions,
parsing pages as user navigates rather than all at once
- Refactor TextBlock/ParsedText from std::list to std::vector,
reducing heap allocations by ~12x per TextBlock and eliminating
crashes from repeated page navigation due to heap fragmentation
- Limit cached pages to MAX_CACHED_PAGES (4) with re-parse capability
for backward navigation beyond the cache window
UI/Layout Fixes (this commit):
- Restore DictionaryMargins.h for proper orientation-aware button
hint space (front buttons: 45px, side buttons: 50px)
- Add side button hints to definition screen with proper "<" / ">"
labels for page navigation
- Add side button hints to word selection screen ("UP"/"DOWN" labels,
borderless, small font, 2px edge margin)
- Add side button hints to dictionary menu ("< Prev", "Next >")
- Fix double-button press bug when loading new chunks by checking
forward navigation availability after parsing instead of page count
- Add drawSideButtonHints() drawBorder parameter for minimal hints
- Add drawTextRotated90CCW() for LandscapeCCW text orientation
- Move page indicator up to avoid bezel cutoff
