Svelte transitions re-trigger on every swap (or don’t run) with manualSwap

[noboike]

When using Swapy with Svelte and manualSwap: true, sorting works fine, but Svelte transitions behave incorrectly:

• On every swap (reorder only), in: / out: transitions sometimes re-trigger as if the item was removed and re-added.
• Other times, transitions don’t run at all after a swap.
• I only expect transitions on add/remove; reorders should use animate:flip and not fire in:/out:.