Daniel 702a7e7a00 fix: remove OOM-causing hrefToSpineIndex map from TOC pass
The unordered_map with 2768 string keys (~100KB+) was causing OOM crashes
at beginTocPass() on ESP32-C3's limited ~380KB RAM.

Reverted createTocEntry() to use original O(n) spine file scan instead.
Kept the safe spineToTocIndex vector in buildBookBin() (only ~5.5KB).
2026-01-20 21:14:05 -08:00
..
2026-01-19 12:56:26 +00:00
2026-01-19 12:56:26 +00:00