The day-boundary notch left its bottom dot lit: the zero baseline is
drawn per braille cell (both dot columns), so it filled in under the
notch's blank column, and the notch connected to the axis instead of
extending down to it. Worse, when the neighbouring bar was tall the
notch's bottom dot took the bar's colour, not even the faint grey.
Introduce a GAP sentinel in braillechart: a timeline column that
renders fully blank — no bar and no baseline — the one deliberate
break in the "grey is zero" flatline. _assemble now decides the
baseline per dot column rather than per cell, so a GAP column goes
blank clean to the axis while its cell-mate keeps its own zero line.
The Time Machine's day charts mark their notches with GAP instead of
None.
A genuine zero-value day still draws its faint grey baseline as
before — only the notch column breaks it.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Jean-Pierre MartineauandClaude Opus 4.8
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