How to share the dependency layer between version updates

The dependency layer will be invalidated when `pyproject.toml` changes. But the dependencies usually remain unchanged when a project bumps version. How to share the dependency layer between version updates?

https://docs.docker.com/build/cache/invalidation/#general-rules

https://github.com/astral-sh/uv-docker-example/blob/6473a50c02f9c36dda8c29cf3e0b6fd84839d353/Dockerfile#L13-L17

Read Dockerfile lines 13-17 and the linked Docker cache invalidation guidance first. Determine how the example can preserve the dependency layer when only the project version changes, then verify that the resulting image build reuses that layer across version updates.

Written by the indexing model from the issue text.