5154: Structured search debugging r=matklad a=davidlattimore
Adds a "search" mode to the rust-analyzer binary that does structured search (SSR without the replace part). This is intended primarily for debugging why a bit of code isn't matching a pattern.
5157: Use dynamic dispatch in AstDiagnostic r=matklad a=lnicola
Co-authored-by: David Lattimore <dml@google.com>
Co-authored-by: Laurențiu Nicola <lnicola@dend.ro>