feat(allocator, linter): store worker thread flags in FixedSizeAllocator

[overlookmotel]

Prepare the way for running JS linter plugins on multiple threads.

Previously we only had to track whether an Allocator's memory was shared with JS main thread or not, so a single flag was sufficient. Once we have plugins running on multiple worker threads, we need to track for each Allocator which JS threads it's been shared with, so can avoid sending the same buffer to the same thread twice.

Store this info as a series of bools stored at the end of the Allocator's memory. FixedAllocator::new initializes all these flags as false when the Allocator is created, and linter checks the flag for the specific thread when it wants to share data with that thread, and sets it to true once buffer has been sent to that thread.

[overlookmotel]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• feat(napi/oxlint): run JS plugins on multiple threads #13244
• feat(allocator, linter): store worker thread flags in FixedSizeAllocator #13136 👈 (View in Graphite)
• refactor(allocator, linter): add ref counter to FixedSizeAllocator #13135
• docs(allocator): correct and expand safety comments on Allocator methods #13139
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13136 will not alter performance

_{Comparing 08-14-feat_allocator_store_worker_thread_flags_in_fixedsizeallocator_ (317698d) with main (8b1e022)¹}

Summary

✅ 34 untouched benchmarks

Footnotes

1. No successful run was found on 08-14-refactor_allocator_linter_add_ref_counter_to_fixedsizeallocator_ (deacd22) during the generation of this report, so main (8b1e022) was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩