Switch to in-tree rustc dependencies with a cfg flag
We can use this flag to detect and prevent breakages in rustc CI. (see #14846 and #15569)
~The `IN_RUSTC_REPOSITORY` is just a placeholder. Is there any existing cfg flag that rustc CI sets?~
Implement builtin#format_args, using rustc's format_args parser
`format_args!` now expands to `builtin#format_args(template, args...)`, the actual expansion now instead happens in lowering where we desugar this expression by using lang paths.
As a bonus, we no longer need to evaluate `format_args` as an eager macro which means less macro expansions overall -> less cache thrashing!
Fixes https://github.com/rust-lang/rust-analyzer/issues/15082
internal: Record import origins in ItemScope and PerNS
This records the import items definitions come from in the module scope (as well as what an import resolves to in an ItemScope). It does ignore glob imports as thats a lot more work for little to no gain, glob imports act as if the importing items are "inlined" into the scope which suffices for almost all use cases I believe (to my knowledge, attributes on them have little effect).
There is still a lot of work needed to make this available to the IDE layer, but this lays out the ground work for havin IDE layer support.
cc https://github.com/rust-lang/rust-analyzer/issues/14079
the "add missing members" assists: implemented substitution of default values of const params
To achieve this, I've made `hir::ConstParamData` store the default values
Fix pinned version of lsp-types
lsp-types published a new patch version that breaks semver with the proposed feature set (this is intended and documented), we unfortunately forgot to specify the patch version for the pinned version so this breaks us.
