Separate core model logic from top-level asset service layer functions

[jjnesbitt]

Depends on #1886

As a part of the audit backend PR, I noticed that we do something peculiar in the change_asset service layer function, which required an undesirable workaround for audit. The change_asset function at its core just calls remove_asset_from_version and add_asset_to_version sequentially. This achieves the desired outcome, but with the following downsides:

1. Each service layer function (including change_asset) contains its own set of checks and filters to ensure the asset being created/modified/destroyed is not malformed. This is largely similar between the services, but they each differ slightly. So when remove_asset_from_version and add_asset_to_version are called from change_asset, they are each making checks that were already made in change_asset, making the overall operation inefficient.
2. This general architecture of calling one service function from another is not ideal, as it means that those two top level service layer functions have the responsibility of both their intended service layer purpose, as well as needing to conform to being called by other service layer functions, which could potentially diverge in use case.
3. The core model logic is intertwined with the service layer functions, making it impossible to elegantly perform the low level model operations without the service layer side effects. This lead to the do_audit flag being introduced into add_asset_to_version and remove_asset_from_version, to workaround this limitation.

This PR separates out the core model logic from those two respective functions, allowing all of them, including change_asset, to utilize them. This removes the need for the do_audit flag, and generally cleans up the asset service layer a bit.

Once #1886 is merged, this can be rebased off master and fully evaluated.

[jjnesbitt]

It seems the current linting errors are from a rule change in ruff, affecting our pytest marks. I'd like to defer that fix to a separate PR.

[dandibot]

🚀 PR was released in v0.3.94 🚀