By using codepoint entities like `'&'` → `"&"`, we have a much
smaller lookup table (58 bytes instead of 29× pointer size ~= 232
bytes). This makes the cache happy, and the benchmark run about ~20%
faster.
```text
$ cargo bench --bench escape
Escaping time: [3.4087 µs 3.4126 µs 3.4168 µs]
change: [-19.790% -19.580% -19.354%] (p = 0.00 < 0.05)
Performance has improved.
```
1017451579