Use pooled StringBuilders to reduce allocations#2074

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Copilot wants to merge 7 commits intomainfrom

copilot/use-pooled-stringbuilder

Commits on Apr 28, 2026

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Copilot
authored
Use a pooled StringBuilder for all instances

Copilot
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twsouthwick
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Address code review: add capacity cap and EnsureCapacity hint

Copilot
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twsouthwick
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Replace ThreadStatic pool with shared DefaultObjectPool-style pool; move to Framework/; use InternalsVisibleTo for Features

Copilot
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twsouthwick
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Add comment explaining ReadOnlySpan constructor use in HexStringFactory

Copilot
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twsouthwick
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Un-chain .Append calls to one per line for readability

Copilot
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twsouthwick
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Fix CS0122: use new StringBuilder() in HexStringFactory instead of internal StringBuilderPool

Copilot
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twsouthwick
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