mount: prefer boot disk ESP and run cargo fmt

* choose ESP matching the primary data disk when multiple ESPs exist,
  falling back gracefully for single-disk layouts
* keep new helper to normalize device names and reuse the idempotent
  mount logic
* apply cargo fmt across the tree

src/main.rs

@@ -56,6 +56,8 @@ fn real_main() -> Result<()> {
         .with_report_current(cli.report_current)
         .with_report_path(cli.report.clone())
         .with_topology_from_cli(cli.topology.is_some())
-        .with_topology_from_cmdline(config::loader::kernel_cmdline_topology().is_some() && cli.topology.is_none());
+        .with_topology_from_cmdline(
+            config::loader::kernel_cmdline_topology().is_some() && cli.topology.is_none(),
+        );
     orchestrator::run(&ctx)
 }