Adding a fast path for TextDecoder latin1

[anonrig]

Latin1 still uses ICU, which is extremely slow. We can add a fast path, just like utf8 and make it extremely fast.

Ref: https://github.com/nodejs/node/blob/main/lib/internal/encoding.js#L424

cc @RafaelGSS

[CarlosEduR]

Nice

[CarlosEduR]

@anonrig could you guide me a little bit on this and/or list me some PRs as reference? Just cloned the repo and taking a look...