Merge #3958

3958: Add proc-macro related config and tests r=matklad a=edwin0cheng

This PR do the following things:

1. Add cli argument `proc-macro` for running proc-macro server.
2. Added support for proc-macro in bench and analysis-stats
3. Added typescript config for proc-macros
4. Added an heavy test for proc-macros.

To test it out:

1. run `cargo xtask install --proc-macro`
2. add `"rust-analyzer.cargo.loadOutDirsFromCheck": true"` and `"rust-analyzer.procMacro.enabled": true"` in vs code config.

[Edit] Change to use `rust-analyzer proc-macro` for running proc-macro standalone process.

Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>

diff --cc Cargo.lock
Simple merge