Blank lines between reasoning/tool/text grew and shrank mid-stream because
spacing was ad-hoc: tools carried marginTop:1, text/reasoning none, and the
markdown text part rendered the model's leading/trailing newlines as transient
blank lines that filled in as deltas arrived.
Now the parts column owns ALL spacing via gap:1 (uniform 1 line between any two
parts regardless of type/order), per-part marginTop is dropped, and text parts
are stripped of leading/trailing blank lines so the gap is the sole source —
no double gaps, no popping. Verified live: Thought/tool/tool/answer all spaced
by exactly one line. (80 pass.)
alt-glitch
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