Map our diagnostics to rustc and clippy's ones
And control their severity by lint attributes `#[allow]`, `#[deny]` and ... .
It doesn't work with proc macros and I would like to fix that before merge but I don't know how to do it.
Split out project loading capabilities from rust-analyzer crate
External tools currently depend on the entire lsp infra for no good reason so let's lift that out so those tools have something better to depend on
- replace tokio's env-filter with a smaller&simpler targets filter
- reshuffle logging infra a bit to make sure there's only a single place
where we read environmental variables
- use anyhow::Result in rust-analyzer binary
This code replaces the thread pool implementation we were using
previously (from the `threadpool` crate). By making the thread pool
aware of QoS, each job spawned on the thread pool can have a different
QoS class.
This commit also replaces every QoS class used previously with Default
as a temporary measure so that each usage can be chosen deliberately.
Drop support for non-syroot proc macro ABIs
This makes some bigger changes to how we handle the proc-macro-srv things, for one it is now an empty crate if built without the `sysroot-abi` feature, this simplifies some things dropping the need to put the feature cfg in various places. The cli wrapper now actually depends on the server, instead of being part of the server that is just exported, that way we can have a true dummy server that just errors on each request if no sysroot support was specified.
