⚡ Bolt: Optimize bounds checking in VirtualMemory hot loops

[manupawickramasinghe]

💡 What

Refactored while loops iterating over Span<T> in TryValidateRange, CopyFromRegions, and CopyToRegions to use standard for loops bounded by span.Length.

🎯 Subsystem & Bottleneck

• Subsystem: Guest MMU & Memory Subsystem
• Target File(s): src/SharpEmu.Core/Memory/VirtualMemory.cs
• Bottleneck Addressed: CPU instruction overhead caused by implicit array bounds checks inside high-frequency memory read/write validation paths. The C# JIT compiler cannot elide bounds checks for while loops with manual index tracking.

📜 Git & Contributor Context

• Recent File History: Checked git log and blame. The targeted methods haven't been recently modified by other concurrent optimizations or contributors in ways that would cause conflicts (the most recent change was an unrelated fix to FindInsertionIndex).
• Conflict Check: Verified change does not overlap with recent commits or reverted attempts.

📊 Measured Performance Impact

• Computational Impact: Replaced manual indexing with a pattern that guarantees $O(1)$ sequential access without runtime bounds checking overhead per element processed.

🔬 Verification Checklist

• Executed dotnet test (All relevant memory tests passed)
• Verified zero unexpected allocations in hot path
• Verified formatting with dotnet format
• Confirmed thread safety and emulation accuracy

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PR created automatically by Jules for task 14843958055350244017 started by @manupawickramasinghe

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📦 Build artifacts — b72e8d8

Platform	Download
Windows (win-x64)	sharpemu-win-x64-1ad764f
Linux (linux-x64)	sharpemu-linux-x64-1ad764f
macOS (osx-x64)	sharpemu-osx-x64-1ad764f

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