add gc support to Rust owned objects

[anonrig]

This PR adds garbage collection support to Rust-owned JSG resources, enabling proper cleanup when V8 collects JavaScript wrapper objects.

Implements Oilpan integration to our Rust/JSG integration. Compared to C++ GC implementation, Rust use cppgc heap for allocation of resources rather than kj::heap. We eventually need to do the same thing in our C++ implementation as well.

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Used AI to help me write comments.

[codspeed-hq[bot]]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing yagiz/rust-gc (cc5611d) with main (dbe7e6f)}

Summary

✅ 129 untouched benchmarks
⏩ 49 skipped benchmarks[^skipped]

[^skipped]: 49 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.

[github-actions[bot]]

The generated output of @cloudflare/workers-types matches the snapshot in types/generated-snapshot :tada:

[anonrig]

I'm taking one step back and prepare an internal document to make the best decision.