fix: use systemd first-boot detection for rollback check

Fixes misleading warning on first boot and on systems with
non-persistent journald storage.

Signed-off-by: Sarita Mahajan <sarmahaj@redhat.com>

Author: sarmahaj

src/main.rs

@@ -167,6 +167,20 @@ where
 fn check_previous_rollback() -> Result<bool> {
     log::debug!("Checking journalctl for previous rollback attempts...");
 
+    // Use systemd's first-boot detection to skip the rollback check on first boot.
+    // This is more reliable than journalctl --list-boots, which would also skip
+    // on systems with non-persistent journald storage.
+    let first_boot_check = Command::new("systemd-analyze")
+        .arg("condition")
+        .arg("ConditionFirstBoot=yes")
+        .output()
+        .context("Failed to execute 'systemd-analyze condition ConditionFirstBoot=yes'")?;
+
+    if first_boot_check.status.success() {
+        log::debug!("First boot detected, skipping rollback check");
+        return Ok(false);
+    }
+
     let output = Command::new("journalctl")
         .arg("-b")
         .arg("-1")
@@ -186,8 +200,7 @@ fn check_previous_rollback() -> Result<bool> {
         return Ok(false);
     }
 
-    let journal_output =
-        String::from_utf8(output.stdout).context("Failed to parse journalctl output as UTF-8")?;
+    let journal_output = String::from_utf8_lossy(&output.stdout);
 
     if journal_output.trim().is_empty() {
         log::debug!("No rollback service logs found in previous boot");