Replace single contiguous miniBitmap allocation with fixed 4KB chunks to allow large font page bitmaps (20-40KB) to fit in fragmented heap. Each glyph is kept whole within one chunk by padding to next chunk boundary when needed. Falls back to overflow path if glyph exceeds chunk size or max chunks reached. Mirrors existing image .pxc slot chunking strategy.
Prevents bold-italic glyphs from rendering blank under heap pressure (when BLE is resident). Pre-allocates a 1KB emergency buffer at font load time when heap is healthy. When per-glyph malloc fails during overflow, falls back to this buffer to render the glyph directly instead of returning null. The emergency buffer bypasses the cache ring and is overwritten on each use, which is safe since getGlyphBitmap() consumes bitmaps immediately.
Previously a single scan buffer was used for all text styles (regular, bold, italic, bold-italic), causing the font decompressor to allocate full-page buffers for each style during prewarming. This led to OOM failures when the BLE stack was resident, causing bold/italic glyphs to render blank.
Now each style maintains its own scan buffer, sized only for the text actually rendered in that style. This keeps secondary style buffers small and prevents allocation failures.
Ties bookmarks to the actual text on the page rather than to a page number. Page numbers shift whenever the book gets re-laid-out — changing font size, margins, line spacing, or rotating the screen — which could previously land you on the wrong spot.
This is a followup of #2805, making bookmarks use the same mechanism. Several minor improvments ride along.
Prevents firmware crashes on ESP32-C3 when parsing CJK text with thousands of tokens. Vector's contiguous reallocation (64-128 KB) fails under fragmented heap with BLE active. Deque grows in ~512 B chunks, keeping max contiguous allocation under 2 KB regardless of token count.
Removes X3ProbeResult struct and associated I2C device detection
functions (probeBQ27220Signature, probeDS3231Signature,
probeQMI8658Signature) along with helper function readI2CReg8 in favor
of an SDK driven device detect API
