[perf] lua - combine finalize filters

[cscheid]

It seems hard to avoid the overhead of coalesce_raw, but we can write by hand a filter that combines its behavior with one of its neighbors on the list. This appears to work well on A/B testing.

$ run_experiment.py main 2025-01-23-finalize-combined deno run --allow-all ~/repos/github/quarto-dev/quarto-cli/tools/run-pandoc-capture.ts render-command.json
┏━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━┓
┃ Variant ┃ Count ┃ Mean     ┃ Std Dev    ┃
┡━━━━━━━━━╇━━━━━━━╇━━━━━━━━━━╇━━━━━━━━━━━━┩
│ A       │ 10    │ 0.591234 │ 0.00634839 │
│ B       │ 9     │ 0.534588 │ 0.00587546 │
└─────────┴───────┴──────────┴────────────┘
{'outcome': 'significant', 'winner': 'B', 'p_value': np.float64(5.109983792608639e-13), 'total_samples': 20, 'alpha_spent': 0.05, 'statistics': {'counts': {'A': 10, 'B': 10}, 'means': {'A': 0.5912335634231567, 'B': 0.5357627630233764}, 'variances': {'A': 4.030205561839084e-05, 'B': 4.3499259748558394e-05}}}
Statistical Summary:
===================
Variant     Count         Mean      Std Dev
-------- -------- ------------ ------------
A              10     0.591234     0.006348
B              10     0.535763     0.006595

[cscheid]

So this one is kind of a bigger win - 10% of the entire Pandoc runtime on this document.