backport: Merge bitcoin#29260, 28191, 27832#7201

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vijaydasmp wants to merge 3 commits intodashpay:developfrom

vijaydasmp:March_2026_7

Commits on Mar 4, 2026

Merge bitcoin/bitcoin#29260: refactor: remove CTxMemPool::queryHashes()

glozow
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vijaydasmp
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Commits on Mar 7, 2026

Merge bitcoin/bitcoin#28191: refactor: Remove unused MessageStartChars parameters from BlockManager methods

fanquake
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vijaydasmp
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Merge bitcoin/bitcoin#27832: doc: Clarify -datacarriersize, add -datacarriersize=2 tests

fanquake
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vijaydasmp
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