add _format_cert_table() helper for CLI cert listings

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

openvpncertupdate.py

@@ -1262,6 +1262,22 @@ class CursesApp:
 # ============================================================
 
 
+def _format_cert_table(certs: list[CertInfo]) -> str:
+    """Render CN / expiry / email as an aligned table, like `ls -l`."""
+    if not certs:
+        return "(no certificates)"
+    rows = [
+        (c.cn, _expiry_label(c).strip(), get_email(EASYRSA_PKI_DIR, c.cn) or "(none)")
+        for c in certs
+    ]
+    cn_w  = max(len("CN"),      max(len(r[0]) for r in rows))
+    exp_w = max(len("EXPIRES"), max(len(r[1]) for r in rows))
+    lines = [f"{'CN':<{cn_w}}  {'EXPIRES':<{exp_w}}  EMAIL"]
+    for cn, exp, email in rows:
+        lines.append(f"{cn:<{cn_w}}  {exp:<{exp_w}}  {email}")
+    return "\n".join(lines)
+
+
 class CliRunner:
     """Non-interactive runner for scripting / cron use."""