Add boot log (#106)

Fixes: #105

Author: bleggett

src/recorders/postinstall/system.rs

@@ -47,6 +47,7 @@ impl SystemRecorder {
             self.record_kernel_cfg().boxed(),
             self.record_xen_capabilities().boxed(),
             self.record_loaded_modules().boxed(),
+            self.record_boot_log().boxed(),
         ])
         .await;
 
@@ -241,6 +242,16 @@ impl SystemRecorder {
         self.run_tool("journalctl -u kubelet").await
     }
 
+    /// Records the current boot kernel journalctl log.
+    ///
+    /// Manual equivalent:
+    /// ```sh
+    /// journalctl -b
+    /// ```
+    pub async fn record_boot_log(&self) -> CheckResult {
+        self.run_tool("journalctl -b").await
+    }
+
     /// Records CPU hardware details and feature flags.
     ///
     /// Manual equivalent: