Ancient Cities are now generating at Y -27 instead of Y -51

Ancient Cities now always generate at Y -27 instead of Y -51 as they did in the previous Bedrock beta/preview, as well as the current Java 22w18a release.

This is a bug. While the ancient city jigsaw files have changed with a starting coordinate at Y -27, the new 22w18a Java generator is designed to generate them downward from that location so they end up at Y -51. However, for whatever reason the Bedrock Ancient City generator is still coded to generate them upward from that position so Bedrock Ancient Cities are generating too high in the world.

Reproducibility: Always

Steps to reproduce:

Go to any Ancient City in Bedrock 1.19.0.30/1.19.0.31. The city will be at a higher Y level than Java.

Suggested seed & coordinates: -1219847014503467214  X: 580 Y: -20 Z: 130

This city is at the same X and Z coordinates in both Bedrock and Java when using this seed and provides a good example of the issue.

Observed results: The city floor places the player at Y -27.

Expected results: The player should be at Y -51 when standing on the city floor.