Automatically generate partial update APIs for eager archetypes

[teh-cmc]

This extends the codegen of the attr.rust.archetype_eager attribute so that it automatically generates partial updates APIs for all eager archetypes.

• DNM: requires Implement support for opt-in eagerly-serialized archetypes #8646
• Part of New partial updates logging APIs: Rust #8581

[github-actions]

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Result	Commit	Link	Manifest
✅	a1331e1	https://rerun.io/viewer/pr/8647	+nightly +main

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