Newly-created memos were pinned to column one and never released, and cards
that grew after placement (late images/comments) never rebalanced, so the
columns drifted badly out of balance.
- Leave the priority (just-created) memo's column assignment transient, so a
superseded memo rebalances instead of piling up in column one forever.
- Self-heal: re-pack from a clean slate when a late height change leaves the
columns lopsided, adopting it only when it meaningfully shrinks the spread.
- Animate only the adopted rebalance; resizes, column-count changes, growth
reflows and first paint stay instant so widths and positions stay in lockstep.
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