Rollup merge of #134491 - compiler-errors:dtor-tweaks, r=lqd

Some destructor/drop related tweaks

Two random tweaks I got from investigating some stuff around drops in edition 2024:
1. Use the `TypingEnv` of the mir builder, rather than making it over again.
2. Rename the `id` field from `Scope` to `local_id`, to reflect that it's a local id, and remove the `item_local_id()` accessor which just returned the id field.

Author: jieyouxu