## Summary
* **What is the goal of this PR?**
Add a debugging script to help developers monitor the ESP32 serial port
directly from a PC.
* **What changes are included?**
Added a new script: scripts/debugging_monitor.py
## Additional Context
While working on a new Crosspoint-Reader feature, it quickly became
clear that watching the ESP32 serial output without any visual cues was
inconvenient and easy to mess up.
This script improves the debugging experience by reading data from the
serial port and providing:
1. A timestamp prefix for every log line (instead of milliseconds since
power-up)
2. Color-coded output for different message types
3. A secondary window displaying a live graph of RAM usage, which is
especially useful for tracking the memory impact of new features
<img width="1916" height="1049" alt="Screenshot_20260126_183811"
src="https://github.com/user-attachments/assets/6291887f-ac17-43ac-9e43-f5dec8a7097e"
/>
---
### AI Usage
Did you use AI tools to help write this code? _**< PARTIALLY >**_
I wrote the initial version of the script. Gemini was used to help add
the Matplotlib-based graphing and threading logic.
## Summary
- Update README with the list of supported languages for EPUB files.
- Update USER_GUIDE with an extended list of supported and unsupported
languages.
## Additional Context
For weeks, I thought this firmware only supported English, because I
remember you saying that full language support would only be possible
after implementing proper font rendering. I also remember mentioning a
separate Korean fork, Vietnamese issues and so on.
All of this made it clear that this system doesn't support my languages.
I was surprised when I saw a Reddit post with a photo of a book in my
native language. Only then I did learn that such languages are
supported. Therefore, mentioning the supported languages would help
future buyers and new users.
---
### AI Usage
Did you use AI tools to help write this code? _**NO**_
## Summary
* **What is the goal of this PR?** Add EPUB 3 support by implementing
native navigation document (nav.xhtml) parsing with NCX fallback,
addressing issue Fixes: #143.
* **What changes are included?**
- New `TocNavParser` for parsing EPUB 3 HTML5 navigation documents
(`<nav epub:type="toc">`)
- Detection of nav documents via `properties="nav"` attribute in OPF
manifest
- Fallback logic: try EPUB 3 nav first, fall back to NCX (EPUB 2) if
unavailable
- Graceful degradation: books without any TOC now load with a warning
instead of failing
## Additional Context
* The implementation follows the existing streaming XML parser pattern
using Expat to minimize RAM usage on the ESP32-C3
* EPUB 3 books that include both nav.xhtml and toc.ncx will prefer the
nav document (per EPUB 3 spec recommendation)
* No breaking changes - existing EPUB 2 books continue to work as before
* Tested on examples from
https://idpf.github.io/epub3-samples/30/samples.html
## Summary
* Consolidate chapter page data into single file
* Header structure of the file stays the same, following the page count,
we now put a LUT offset
* The page data is all then appended to this file
* Finally the LUT is appended to the end of the file, and the page count
is updated
* This will also significantly improve the duration of cache cleanup
which takes a while to scan the directory and cleanup content
* Remove page file version as it's all tied up into the section file now
* Bumped section file version to 7
* Moved section content into sub directory
* Updated docs
## Additional Context
* Benchmarks:
* Generating 74 pages of content from a chapter in Jade Legacy took:
* master: 6,229ms
* this PR: 1,305ms
* Speedup of 79%
* Generating 207 pages of content from Livesuit book:
* With progress bar UI updates:
* master: 24,250ms
* this PR: 8,063ms
* Speedup of 67%
* Without progress bar UI updates:
* master: 13,055ms
* this PR: 3,600ms
* Speedup of 72%
