Auto merge of #63462 - matthewjasper:hygienic-builtin-derives, r=petrochenkov

Auto merge of #63462 - matthewjasper:hygienic-builtin-derives, r=petrochenkov

Opaque builtin derive macros

* Buiilt-in derives are now opaque macros
    * This required limiting the visibility of some previously unexposed functions in `core`.
    * This also required the change to `Ident` serialization.
* All gensyms are replaced with hygienic identifiers
* Use hygiene to avoid most other name-resolution issues with buiilt-in derives.
    *  As far as I know the only remaining case that breaks is an ADT that has the same name as one of its parameters. Fixing this completely seemed to be more effort than it's worth.
* Remove gensym in `Ident::decode`, which lead to linker errors due to `inline` being gensymmed.
    * `Ident`now panics if incremental compilation tries to serialize it (it currently doesn't).
    * `Ident` no longer uses `gensym` to emulate cross-crate hygiene. It only applied to reexports.
    * `SyntaxContext` is no longer serializable.
    * The long-term fix for this is to properly implement cross-crate hygiene, but this seemed to be acceptable for now.
* Move type/const parameter shadowing checks to `resolve`
    * This was previously split between resolve and type checking. The type checking pass compared `InternedString`s, not Identifiers.
* Removed the `SyntaxContext` from `{ast, hir}::{InlineAsm, GlobalAsm}`

cc #60869
r? @petrochenkov