Better user-facing compile-time errors using `#[diagnostic]`

[Adamkob12]

What problem does this solve or what need does it fill?

Currently, due to the heavy use of all_tuples (Bundling up generic types in tuples) in traits like Bundle, SystemParam, IntoSystemConfig, user-facing compile time errors can get very messy and uninformative.

For example (the actual problem was caused when forgetting to implement Component for some type):

But it's gonna be very hard for inexperienced users to understand what the problem is, and how to fix it.

What solution would you like?

Version 1.78 introduced #[diagnostic] attributes. We can use #[diagnostic::on_unimplemented] to make those errors more informative and readable.

[alice-i-cecile]

Duplicate of #12377 :) Strongly desired though!