Tracking issue: dynamic APIs and reflection improvements for scripting

[jakobhellermann]

• [Merged by Bors] - untyped APIs for components and resources #4447
• *const () -> &dyn Reflect ([Merged by Bors] - bevy_reflect: ReflectFromPtr to create &dyn Reflect from a *const () #4475)
• by_id component insertion/deletion (currently very tied to rust types and bundles)
• untyped query (UntypedQuery::new().read(component_id).write(component_id).without(component_id) ?)
• struct reflect instead of value for VecN (so that .x paths work) ([Merged by Bors] - Add macro to implement reflect for struct types and migrate glam types #4540)

[PROMETHIA-27]

I could try to make a PR to address the reflect type for VecN. Seems like an easy enough change

[alice-i-cecile]

Closing in favor of Reflection <3