Make an embedded-in-`.rs` SQL pretty-printer

[trevyn]

Separate binary that can be run that uses syn to parse out .rs files, replace strings with SQL with pretty-printed, then run rustfmt afterwards. Can swap this in with rust-analyzer.rustfmt.overrideCommand.

See also: https://crates.io/crates/sqlformat and https://crates.io/crates/prettyplease

[trevyn]

Also see DioxusLabs/dioxus#368 for an example of pretty-printing macro contents in a VSCode extension