## Summary
* Rely on media-type="application/x-dtbncx+xml" to find TOC instead of
hardcoded values
## Additional Context
* Most of my epubs don't have id==ncx for toc file location. I think
this media-type is EPUB standard
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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
## Summary
- When allocating the `bwBuffer` required to restore the RED RAM in the
EPD, we were previously allocating the whole frame buffer in one
contiguous memory chunk (48kB)
- Depending on the state of memory fragmentation at the time of this
call, it may not be possible to allocate all that memory
- Instead, we now allocate 6 blocks of 8kB instead of the full 48kB,
this should mean the display updates are more resilient to different
memory conditions
## Additional Context
