Add Rendering tests for Multi Draw Indirect

[Sirtsu55]

This PR adds new operation/rendering tests for MDI. I had these done a while ago and finally found time to open a PR!
There aren't many tests added, but this should aid the development of other tests.

Issue: #3961

---

Requirements for PR author:

• All missing test coverage is tracked with "TODO" or .unimplemented().
• New helpers are /** documented */ and new helper files are found in helper_index.txt.
• Test behaves as expected in a WebGPU implementation. (If not passing, explain above.)
• Test have be tested with compatibility mode validation enabled and behave as expected. (If not passing, explain above.)

Requirements for reviewer sign-off:

• Tests are properly located in the test tree.
• Test descriptions allow a reader to "read only the test plans and evaluate coverage completeness", and accurately reflect the test code.
• Tests provide complete coverage (including validation control cases). Missing coverage MUST be covered by TODOs.
• Helpers and types promote readability and maintainability.

[kainino0x]

@Sirtsu55 it seems like there are some other changes mixed up in here due to some rebase/merge problem, could you fix that up?

If all of the changes you want are in the one commit, you can:

git checkout main
git pull
git checkout multidraw-tests
git reset --hard main # this will drop all changes from the branch!
git cherry-pick cbcb9d3 # this will bring back just the one commit
git push -f # overwrite the branch on github