Map inet columns to IpAddr through sqlx.toml

Every `inet` column holds a single host address, so a type override in
the new per-crate `sqlx.toml` replaces the `as "col: IpAddr"` casts the
queries needed to avoid the default `IpNetwork` mapping. Both crates
using the query macros also pin `chrono` as the date/time crate.

This needs the `sqlx-toml` feature on `sqlx`. `sqlx-cli` needs it too,
as it refuses to run in a crate directory that contains a `sqlx.toml`
file otherwise. It is a default feature of `sqlx-cli`, so only the
`--no-default-features` install in the docs has to name it.

docs/development/database.md

@@ -30,14 +30,19 @@ Usually it does so by having the database available at compile time, but to avoi
 Preparing this flat file is done through `sqlx-cli`, and should be done everytime the database schema or the queries changed.
 
 ```sh
-# Install the CLI
-cargo install sqlx-cli --no-default-features --features postgres
+# Install the CLI. The `sqlx-toml` feature is required because the CLI refuses
+# to run in a crate directory that contains a `sqlx.toml` file without it.
+cargo install sqlx-cli --no-default-features --features postgres,sqlx-toml
 
 cd crates/storage-pg/ # Must be in the mas-storage-pg crate folder
 export DATABASE_URL=postgresql:///matrix_auth
 cargo sqlx prepare
 ```
 
+Both `mas-storage-pg` and `syn2mas` use the query macros and have their own
+`.sqlx` cache and `sqlx.toml`. The `misc/sqlx_update.sh` script regenerates both
+in one go (it also sets up the temporary tables `syn2mas` needs).
+
 ## Migrations
 
 Migration files live in the `migrations` folder in the `mas-storage-pg` crate.