The spec claimed the math pane and the signal list were two lists of the same
channels; they are one. `append_math_signals_locked()` already puts every math
channel into `signals()` and nothing filters `sig.math`, so the merge is mostly
a deletion -- the list gains a `MATH` divider and a second menu, and the pane
goes. §2, §3 and §6 say so now.
The plan is seven tasks, each ending in a build, `make test-ui` and one short
headless probe read.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Five revealers in one column leave every section short of room once the
trigger, cursors, measurements and math panes are open. The design splits
the column into two tabs, folds the math list into the signal list -- the
two were the same list drawn twice -- and makes a feature's toggle disable
its pane rather than hide it, because a tab cannot carry an on/off.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
