Signal handling for non-Python WASM modules

[logan-gatlin]

Adds a shim around WebAssembly.Instance and WebAssembly.instantiate which checks for signal handling capabilities. If present, grab a reference to the module's linear memory, and pass along signals to it. Currently the only supported signals are a CPU limit warning (sent from the host) and a termination notice (set by the module to indicate it has aborted).

In order to receive signals, a module must export a global i32 address called "signal_address_v1" into linear memory, and either import or export a memory called "memory". The CPU limit warning is at signal_address_v1[0], while the termination notice is expected to be at signal_address_v1[1].

[github-actions]

All contributors have signed the CLA ✍️ ✅
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[logan-gatlin]

I have read the CLA Document and I hereby sign the CLA

[logan-gatlin]

Looks like rebase messed up the history

EDIT: fixed

[codspeed-hq]

Merging this PR will not alter performance

✅ 70 untouched benchmarks
⏩ 129 skipped benchmarks¹

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_{Comparing logan-gatlin:logan/wasm-signal-handling (544048a) with main (02c8669)}

Footnotes

1. 129 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. ↩