doc: Add an auto-generated dependency graph for internal crates

[2010YOUY01]

Which issue does this PR close?

• Closes #.

Rationale for this change

A dependency graph for workspace member crates are often needed when doing refactors, I want it to be included in the doc, and have a script to update it automatically.

Here is the preview:

What changes are included in this PR?

• adds a script to generate the dependency graph deps.svg, and verify if the existing one is up to date.
• adds a documentation page in Contributor Guide to show this graph
• adds a CI job to check if the generated dependency graph is up to date with the code.

Are these changes tested?

I tested the dependency graph display locally, see above. Is it possible to see the preview from this PR's change online?

I also included a dummy crate in the initial commit, to test if the CI can catch it and throw understandable error message.

Are there any user-facing changes?

No