copy fill value before reallocation in array::insert/resize

[Ramya-9353]

Repro: on a full array, a.insert(a.begin(), n, a[0]) or a.resize(n, a[1]) reads freed memory (ASAN heap-use-after-free in the value copy constructor).
Cause: revert_insert relocates the elements into a newly allocated table and frees the old one before the fill loop runs, so a value that aliases an existing element is left dangling.
Fix: copy the value into a local before constructing revert_insert, the same snapshot object::emplace_impl and array::emplace already take. std::vector defines these self-referential fills, so the copy overloads should honour it too.

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2026-07-07 07:42:49 UTC

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Build time: 2026-07-07 07:51:37 UTC

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