Binary graph renders differently for historical vs live data

[iTerminate]

The binary sensor graph appears to render in a different visual state depending on whether it's showing historical data (loaded from history fetch) vs live data (streamed state_changed events). The plot should stay in one consistent rendering state for the whole duration it's displaying historical data, rather than flipping style once live data starts arriving.

Likely in `src/hatty/ui/graph/plot_render.py` (`render_binary`/`set_binary_axis`) or `src/hatty/ui/graph/entity_detail.py` (`update_binary`/`_render_binary_mode`).