Replace memo queue with append-only vector

[ibraheemdev]

Should be an easy win here.

[netlify]

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[codspeed-hq]

CodSpeed Performance Report

Merging #767 will not alter performance

_{Comparing ibraheemdev:memo-queue (6c18ee8) with master (e826b5a)}

Summary

✅ 12 untouched benchmarks

[ibraheemdev]

I guess this will be obselete if #660 ever lands.

[ibraheemdev]

Weirdly, 47f8917 on its own was a 5% improvement before the boxcar update.. now it's a regression, despite #696 showing an improvement.

[Veykril]

I believe our benches have become fast enough that they turn noisy again unfortunately, especially report_tracked_read jumps randomly and that code is inserting into a hashmap, so its likely allocation noise still.

[Veykril]

I suppose this resolves #733?

[MichaReiser]

This looks good. I'll hit the merge button because @ibraheemdev isn't a contributor yet (we should bring this up in our next salsa meeting or on zulip)