Upgrade proxy crates to edition 2024 (#10942)

This upgrades the `proxy/` crate as well as the forked libraries in
`libs/proxy/` to edition 2024.

Also reformats the imports of those forked libraries via:

```
cargo +nightly fmt -p proxy -p postgres-protocol2 -p postgres-types2 -p tokio-postgres2 -- -l --config imports_granularity=Module,group_imports=StdExternalCrate,reorder_imports=true
```

It can be read commit-by-commit: the first commit has no formatting
changes, only changes to accomodate the new edition.

Part of #10918

proxy/src/serverless/json.rs

@@ -1,5 +1,5 @@
-use postgres_client::types::{Kind, Type};
 use postgres_client::Row;
+use postgres_client::types::{Kind, Type};
 use serde_json::{Map, Value};
 
 //