bevy_utils: Export generate_composite_uuid utility function

[MrGVSV]

Objective

The generate_composite_uuid utility function hidden in bevy_reflect::__macro_exports could be generally useful to users.

For example, I previously relied on Hash to generate a u64 to create a deterministic HandleId. In v0.12, HandleId has been replaced by AssetId which now requires a Uuid, which I could generate with this function.

Solution

Relocate generate_composite_uuid from bevy_reflect::__macro_exports to bevy_utils::uuid.

It is still re-exported under bevy_reflect::__macro_exports so there should not be any breaking changes (although, users should generally not rely on pseudo-private/hidden modules like __macro_exports).

I chose to keep it in bevy_reflect::__macro_exports so as to not clutter up our public API and to reduce the number of changes in this PR. We could have also marked the export as #[doc(hidden)], but personally I like that we have a dedicated module for this (makes it clear what is public and what isn't when just looking at the macro code).

---

Changelog

• Moved generate_composite_uuid to bevy_utils::uuid and made it public
  • Note: it was technically already public, just hidden

[github-actions]

Your PR increases Bevy Minimum Supported Rust Version. Please update the rust-version field in the root Cargo.toml file.

[alice-i-cecile]

Fascinating, any idea why this would increase MSRV?

[MrGVSV]

Fascinating, any idea why this would increase MSRV?

No clue haha.

The first CI run failed the MSRV check due to an ambiguous module name (uuid). Maybe the comment is from that failure and not the latest pass?

Any insight @mockersf?

[alice-i-cecile]

@MrGVSV can you please merge main in so you can get the new CI check?