fix(rust): drop the stray spaces in the running-server handoff line

The D156 line printed "confirms it                  connected." — a
wrapped source line left a run of spaces inside the string literal.
Found by the phase 18 step 7 re-walk on Debian 12.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

src/rustgame/sidecar.rs

@@ -185,7 +185,7 @@ pub fn handoff(
         protocol = doc.protocol,
         when = if running {
             format!(
-                "The plugin loads now; `doctor --game rust --server-id {server_id}` confirms it                  connected."
+                "The plugin loads now; `doctor --game rust --server-id {server_id}` confirms it connected."
             )
         } else {
             "The plugin connects when the server next starts.".to_string()