Add fabinout codec: 7,283,778 bytes

[Fabinout]

Row-oriented store with global dictionaries and Zstd compression.

This code has been heavily written by IA, my goal was to understand how codecs work and how compression worked in small scale. Feel free to reject it if you're unconfortable.

For maximum transparency, i used Claude as co-author of the commit.

[agavra]

Confirmed via CI run. Thanks for the submission @Fabinout - AI is definitely welcome :) no reason to shut out the future

[2](https://github.com/agavra/compression-golf/actions/runs/21522332314/job/62020044593?pr=9#step:8:23)
┌────────────────────────┬────────────────┬────────────┐
│ Codec                  │           Size │ vs Naive   │
├────────────────────────┼────────────────┼────────────┤
│ Naive                  │    210,727,389 │   baseline │
│ fabinout               │      7,283,778 │     -96.5% │
└────────────────────────┴────────────────┴────────────┘