Webserver:
- Remove MD5 hash computation from file listings (caused EAGAIN errors)
- Implement JSON batching (2KB) with pacing for file listings
- Simplify sendContentSafe() flow control
Memory:
- Cache QR codes on server start instead of regenerating per render
- Optimize WiFi scan: vector deduplication, 20 network limit, early scanDelete()
- Fix 48KB cover buffer leak when navigating Home -> File Transfer
EPUB Reader:
- Fix errant underlining by flushing partWordBuffer before style changes
- Text before styled inline elements (e.g., <a> with CSS underline) no longer
incorrectly receives the element's styling
Flash Screen:
- Fix version string buffer overflow (30 -> 50 char limit)
- Use half refresh for cleaner display
- Adjust pre_flash.py timing for half refresh completion
