The "Spots + background" dataset plot now scales each quantity on its own
axis - background on the left, spot count on the right - with each axis's
labels and line coloured like its curve, so which axis reads which quantity
is visible at a glance. Each axis is ranged from its own series alone, so
live growth of one quantity never rescales the other; on top of that the
background's range is inflated upward and the spot count's downward, each by
its own span, so the two curves occupy separate halves of the plot instead of
crossing. The spot count stays the primary series (current-image marker,
hover, click-to-load, overlays). Trade-off accepted: the spots axis shows
ticks below zero in its empty lower band.
The per-image plot selector no longer offers the X-ray fluorescence spectrum;
the reader-side fluorescence plumbing is untouched.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WbjnQhutnboy4qbxwmgDAX