State-reset and security mitigations.

Upgrade Ruma to present.

The following are intentionally benign for activation in a later commit:

- Hydra backports not default.
- Room version 12 not default.
- Room version 12 not listed as stable.

Do not enable them manually or you can brick your database.

Signed-off-by: Jason Volk <jason@zemos.net>

src/core/Cargo.toml

@@ -119,7 +119,9 @@ hardened_malloc-rs.workspace = true
 hardened_malloc-rs.optional = true
 
 [dev-dependencies]
+insta.workspace = true
 maplit.workspace = true
+similar.workspace = true
 
 [lints]
 workspace = true