fix(gossipsub): optimize IDONTWANT send

[jxs]

Description

avoid sending redundant IDONTWANT messages by only sending IDONTWANT for first-seen large messages and deduplicating recipient peers with a HashSet.

[mergify]

This pull request has merge conflicts. Could you please resolve them @jxs? 🙏

[ackintosh]

Looks good to me!

[mergify]

Merge Queue Status

• ✅ Entered queue — 2026-03-24 22:43 UTC · Rule: default
• ✅ Checks skipped · PR is already up-to-date
• ✅ Merged — 2026-03-24 22:44 UTC · at c60a2d8538936614cd26bacbd21a33fe7ac5efa4

This pull request spent 6 seconds in the queue, with no time running CI.

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  • fix(gossipsub): optimize IDONTWANT send #6356
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  • fix(gossipsub): optimize IDONTWANT send #6356
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