fix(sidecar): apply rustfmt to the protocol 3.0 cutover code

The release workflow's first gate is `cargo fmt --check`, and the 3.0
cutover merge (2301c57) landed two rustfmt violations in the
`world.ruleset` path, so the run failed before it could build or tag:

- main.rs: the `upsert_ruleset(..)` call fits on one line
- store.rs: the `upsert_ruleset` signature does not

No behavior change — formatting only.

Co-Authored-By: Claude <noreply@anthropic.com>

sidecar/src/main.rs

@@ -262,11 +262,7 @@ async fn main() -> anyhow::Result<()> {
                     // lets a reader tell a re-send from an actual config change.
                     "world.ruleset" => {
                         if let Err(e) = event_store
-                            .upsert_ruleset(
-                                ev.value.get("rev").and_then(|r| r.as_str()),
-                                &text,
-                                t,
-                            )
+                            .upsert_ruleset(ev.value.get("rev").and_then(|r| r.as_str()), &text, t)
                             .await
                         {
                             tracing::warn!(error = %e, "failed to upsert ruleset");