Update documentation

[grst]

• in template_usage, several markdown links are broken some markdown links in docs are not correctly rendered #407
• update template sync section
  • document that template repos are registered in ecosystem-packages
• update info on hatch, incl. adding more background.
• show how to use pip or uv with hatch
• add "uv" tab for building docs

Close #330
Close #378

Update scverse-bot repos before making release (see #401):

• https://github.com/CSOgroup/torchgmm/pull/9
• https://github.com/joechanlab/scDeBussy/pull/2

[github-actions]

A PR has been generated to the instance repo:
scverse/cookiecutter-scverse-instance#206

You can check out the PR to preview your changes
in an instance of the cookiecutter template. The PR will be kept in sync with
this PR automatically.

[grst]

Pending final changes based on #424, other than that I think this is ready.

[flying-sheep]

Looks good!

I fixes some typos and made sure the line breaks are on semantic boundaries. This helps to keep diffs smaller.

I also changed :::{admoniton} with :class: tip to an actual :::{tip} as that CSS class is an implementation detail and not an API AFAIK