Prepackage h5ad visualization, publish, formalize requirements.

[dannon]

xref #18530, possible the build at .org is wonky -- this takes that out of the equation, improves startup time, etc.

How to test the changes?

(Select all options that apply)

• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.

[mvdbeek]

I've deployed this on main

[mvdbeek]

No luck with the standard procedure

[guerler]

Now that we have revised our visualization framework. I recommend to implement this without the legacy charts entry_point but as a standalone visualization using the script entry point. I took a stab at it here: galaxyproject/galaxy-visualizations#7. If it looks good to you, feel free to publish and then let's adjust this PR. Thank you for working on this!