feat(allocator): optimize memory usage with dual allocator pools for import plugin

[camc314]

Add AllocatorPool::new_dual() to support both standard and fixed-size allocators
in a single pool, allowing runtime selection based on file purpose. This reduces
memory usage when using the import plugin by using standard allocators (~few MB)
for dependency files that are only parsed for module resolution, while reserving
fixed-size allocators (~2 GiB address space) only for entry files that need
linting with JS plugins.

Fixes #15799

[camc314]

• feat(allocator): optimize memory usage with dual allocator pools for import plugin #15802 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #15802 will not alter performance

_{Comparing c/11-17-feat_allocator_optimize_memory_usage_with_dual_allocator_pools_for_import_plugin (37e4ce9) with main (e346426)}

Summary

✅ 42 untouched
⏩ 3 skipped¹

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[overlookmotel]

We've decided not to pursue this. #15799 (comment)